Speaker boxes. To rebuild or not to rebuild

Morning gang,
I picked up a free set of Technics 3 way SB-2860. I cant get any good sound out of them. No bass and all tinny.
Is there a speaker rebuild kit on a website that I can buy drivers, mids and tweeters as a kit? Any recommendations? These wont be my premier set, so we can go average on the expense. But, I think the cabintes are in very good shape and it would be a waste just to toss  them?
Thank you
You could as saiod, Frakenspeaker them.

Or contact Technics and do the rebuild yourself from orig or current drivers and x overs.

You might get lucky and find that technics still has a line on orig parts for them. Some makers do. Some do not. Wouldn’t hurt to make a call and find out.

As was said, there’s a real learning experience in there somewhere just waiting.

Great great suggestions. I am currently performing "open box" surgery to learn and observe the operation of a 3 way. After reading countless threads on many topics, I feel that I can put them to use as donors and then put them out to pasture. I would rather spend the $ on FS52 or Elac F6.
Thank you to all!!
If the cabinets are in a very good shape and you can find the crossover data, do some research to find the right replacement drivers from the site mentioned earlier and you could end up with a great pair of speakers and learned a lot along the way. Win win.
If the cabinets are in good shape, they are probably worth a re build.  They are a 15 inch 3 way from the 1980's from a rack system.  Tweeters are a 3 inch cone, mid is a 5 1/4 inch cone.... cheap electrolytics in the crossover.  I wouldn't mess with a repair period.  If the boxes look good,  I'd probably salvage the woofers, replace the mid & tweeter and customize a simple crossover.  You could get very satisfying results.