Well they have already confirmed Neo Geo VC releases, and I'm pretty sure the later titles are around 70MB or so. I'm pretty sure Dracula X would be half that size, of that, as long as they MP3ed the music.
The actual game data of even the hugest PCE CD is incredibly small. Much much smaller than, say, N64 games, which they are already doing.
The technical side is a non-issue as I can see it. Its really just a matter of willingness, and that is truly up in the air.