Should I

Yes, they're at or past their expected life (in terms of meeting like new spec) But- I wouldn't sink the money into it. Buy a much newer pre-owned amp instead. There are dozens that are as good or far better and are pretty affordable. 

I remember those amps well.  That was the first really nice amp I heard.  I don’t know about recapping, but that is a very high quality amp and worth keeping up with whatever it needs.  I totally disagree that you will find any used amp that’s even remotely close to that level of quality in the affordable category.  Good luck!

Capacitors can fail suddenly, and spectacularly.  That can cause damage to other components, not excluding speakers.  These amps run hot and after 30 years the caps will be well cooked, dried out and ready to blow.

Why not take it back to Rowland and have them re-cap it

I have 2 Model 12's, a model 201 and 102 I bought in 2009. Never even thought of that! I'll contact Jeff...Thx. 

As some suggested, caps have a limited life span and, yes, heat is a factor. You are sitting on a ticking time bomb. Like a new puppy, I wouldn’t go off and leave this amp with the power engaged for too long. You might find yourself with a new high wattage space heater, or a high voltage DC generator designed to push your speaker’s raw drivers forward with great velocity and hold them in place until the voice coils melt.

Otherwise, happy listening.

Yeh, I’d check into having Rowland recap them.