If the 302 bottom end is in good shape, you could leave it alone or rebuild that too, as Geof decided to. If I was going to do that, I would stroke it to 331 (perhaps a tiny bit more with an associated re-bore). On most accounts, that I have read, the 331 is a nice balance for the small block with good torque and also a good rev range (depending on the final drive ratio that you have). It also is said not to put as much stress on the longevity of the SB motor, as can a 347 or larger displacement.
I think I'd have to agree with Merv on this one....331 creates less lateral stress......and if you were going for a 347 stroker using a standard block....they are o.k. as long as you aren't wanting to do much Track work...but if you were , then go the Dart..( Dart Block).
I've FINALLY learned this the hard way after splitting TWO 347 windsors in half.
Cheers,
Warren