Don't get an emulator, it's illegal.
Really, there are only two feasable places to get it. You could go to a local resale shop and look for it (like Disc Replay or a pawn shop), or find it online. The major gaming retail stores like Gamestop won't sell anything older than Gamecube/PS2/XBox games. I imagine it wouldn't cost much more than $40 for the game and the system.