I wouldn't doubt it for a second if they priced KH: COM for 50 dollars. It's a PS2 game now, so I doubt they will have the price cheaper just because it's been out before.
& Most likely, just to make everyone spend more money, they'll put KH2 FM & COM in the same box and make you pay 80 or more. I personally don't want to buy another game that's almost exactly the same for 50 dollars itself just for COM. I mean, I'll probably do it. But it'd make my life so much easier if they sold COM separately if/when it comes out in NA & watch the extra cutscenes in FM on youtube.