30 yr old speakers- time to replace drivers?

I have a pair of Bozak Urban 301 that are 60+ years old that I enjoy the heck out of.  After I inherited them from my father circa 1993, I have had both 12” woofers reconed, and refoamed; replaced one tweeter ( because I damaged it accidentally) bought on eBay; replaced the crossovers with OEM with the Pat Tobin mod, also bought on eBay; rewired internally; and, refinished the cabinetry. Total cost—not counting my own labor—I estimate to be less around $1000-$1200, spread out over a period of about 20 years because I didn’t do it all at once. For instance, I just had one of the woofers reconed and refoamed for about $75 plus shipping. And, these speakers sound fabulous. I have no way of comparing them to contemporary speakers, but as long as I’m happy with their sound, that doesn’t matter.

As an aside, I recently had my Thorens TD124, that I also inherited from my father, rebuilt to look and perform as if brand new, but for about 3 times the cost of the speaker refurb. I still have his Pilot amplifier to have rebuilt, but for now, I’m enjoying playing music on my vintage turntable, through my vintage speakers, attached to my “modern” Yamaha home theater amp. 

My point being: if one derives  pleasure from  “vintage” speakers, it doesn’t cost that much to have them refurbished when and if necessary to keep on enjoying them. 

Thx for all the input. As of right now, I think I’ll go on the one thought, if it’s not broke, don’t fix it. They still sound pretty good. Besides, they’re only used as my surround speakers at this point, so thanks everyone. Down the road if necessary, I’ll upgrade with modern technology 

If the speakers are all working, with no defects, not sure it's worth touching. 

However, the XO might be in need of an update. yes, caps can last decades, even out of spec can work almost perfectly. Just replaced the caps in my XO's, while my speakers sounded just fine, after swapping out the 10 caps (5x per speaker) WOW, like OMG WOW, sounds like a new set of speakers! Way more bass, way tighter bass, silky midrange, high top end. My tone controls needed to be reset, tweeter went from +3 to 0 bass went from +6 to +3. 

It was the best $50 and 2hrs of work ever spent in my system. 

I don't understand the logic with some on here saying don't put money into 30 year old speakers and don't fix it if isn't broken.  Well, I went exactly against all this advice and put money into an old pair of Infinity Kappa 9's nobody wanted. 

I spent $200 for the speakers in rough shape that were missing 3 out of 4 of the 12" woofers and the polydome mids were trashed.  They were made in 88'-89' so about 35 years old, the crossovers needed attention and that's where the new life came back for them.  Some tweeters were not working as result of the crossovers failing. I fixed everything and replaced every capacitor, about 23 total per speaker.  It was about $700 in capacitors and I have about $1300 into them.  I find they sound phenomenal now, brought the efficiency up fixing the crossovers.  Capacitors definitely go bad, drivers if the surrounds are still good, you're good there. 

Do what you feel is right and your budget can handle.  I know there's always better speakers out there than your NHT or my Kappas, but for me it was the right decision to fix up and not buy newer for much more.  I smile everytime I fire up the Kappa 9's paired the Parasound JC-5 amp, Ayre KX-5 Twenty preamp and my little budget Schitt Bifrost 2/64 DAC.  I'd like to add another JC-5 and some Rythmik subs and maybe get into streaming one day.  But for now what I have will do..  I'm not made of money, going out and seeking new speakers wouldn't have been a good decision, but $10k for the amp and preamp was...and so was fixing the 'old' speakers..

I have a pair of Infinity 7 Kappa’s i bought new in 1992 that I power with a Yamaha M70 amp I purchased new  in 1983 when I was 23 years old. I had the amp recapped for $350.00 by a local shop recently, in Dallas. I had  the subs refoamed a damping upgrade added to the spiders and the polydomes rebuilt by Miller Sound in Pennsylvania(they have the parts to fix the polydomes made) for a total cost of speaker repair $405.00. I swear they sound better than new. The kappas are as beautiful as the day I bought them. This system has a very warm sound and is perfect for my family room. I do have a listening room/Man Cave with Zu Omen def supremes powered by a Pass Labs XA 25 amp that is obviously superior by most any measure, but with DAC and streamer added in is an $18,000.00 investment. While I love the Zu ODS/Pass Labs system if I didn't have a spare 20k including cabling laying around I could live with my old system and be happy. I say if you like the sound of your system tune it up and save some cash.