If you read carefully (or I am blind), you haven't told us which model you actually have. You first say you need codes for the 303CD, later list the model numbers, but never point out which one you have.

Of course, only seven people in the universe have this anyway. Just looking for clarity.

Is CARY a big enough outfit that they actually made the units? How about calling them up and asking them if Funai made them? I have seen a lot of totally mediocre Funai product, so maybe that name might get their blood boiling enough to make them reveal the true manufacturer, and maybe you could get some info there. You would probably have to have some communication between Cary and the real manufacturer for them to release info to you, but it might work.