Spades or bananas? I used to be spades, now bananas. I'd originally been talked into spades being the better connection, but further research kinda blurs all that? Good bananas work well, are convenient, etc. Wire? Practically everything will be OFC, so once you get to 14GA or thicker you're really into diminishing returns. There are still gazillions of opinions about very high strand counts vs. solid vs. whatever, but at practical $$$ that stuff just doesn't matter much. Practically any good 14GA or thicker within your price range will do fine. I've used older Monster fat wire (well, it was a gift..), have tried generic 14GA, snooty/fancy braided cables, Carol 12GA outdoor (the stuff for low voltage lighting), HD 12GA outdoor extension wire, 12GA SoundKing w/ spades (and later Dayton bananas), and my feeble ears couldn't really tell a difference. My inability to distinguish all the finer nuances of wire may be due to prior misspent youth, the fact that I'm over 30 (but by just a little ;~), or that it was all good.
Here's just one example of what would fit your price limit for a 15' bi-wired set (2 pairs, shipped): Parts Express Speaker Wire w/ Bananas Or, just get SoundKing & bananas?
And I won't comment further on bi-wiring, except to point out what a wiring purveyor like Cobalt Cables has to say about that: Cobalt Cables. As usual, YMMV, etc. etc.
Here's just one example of what would fit your price limit for a 15' bi-wired set (2 pairs, shipped): Parts Express Speaker Wire w/ Bananas Or, just get SoundKing & bananas?
And I won't comment further on bi-wiring, except to point out what a wiring purveyor like Cobalt Cables has to say about that: Cobalt Cables. As usual, YMMV, etc. etc.