That's pretty cool. I loved Karate Champ as a kid, and I'd chip in for this.
Yeah, a pressed version would be cool. Just get it ready for pressing, and people will pay for the pressing cost.
As for pricing, if I were a homebrewer, I'd do a voluntary "pay what you will model" -- say anything over $5+shipping. That way, you won't have 500 copies sitting in your living room, your game gets a bit more circulation, and you probably won't even end up losing out monetarily because you'll probably sell quite a bit more in the end. That's gotta be a win-win situation for everyone.
And if people cough up a little more (say $20+), then throw a little something extra (i.e. signature). That way, there's never room for people to pull a RoyVegas or anything since a signed copy is never limited in volume.
Hell, from the talks here, it seems like you can even let other people do the distribution work if you don't want to bother with that.