I just checked eBay and I saw a lot of copies of FFVII with their current bids at around $5. Are you looking for a black label copy of the game? Because yes, that will be more expensive, but its not really necessary. I have a greatest hits version, and guess what? Same game.

Anyway, I know those prices will go up as the auction goes on, but it will probably end up being around $10 or $15 for the game. Definitely, definitely worth it.

I got lucky. Mine was included (along with FFVIII and FFIX) when I bought my PS1 bundle on ebay...for $20.