Wow... Yeah, I hadn't seen a C=264 before, outside of old magazine ads mentioning it as upcoming. It does appear there are a few out there in the wild. A quick google confirmed someone has already captured a ROM image of one, so that is cool. I guess they're out there, I just hadn't seen one before.
(@save2600 - the C65 is fairly well known, and prototypes for it surface surface for sale once a year or so... It's got a somewhat legendary status around here, for some reason.)