@lordkhan The mount is a C/CS lens mount which. Other mount systems people have made adapters for are Pentax K, Canon, and Pentax 110 lenses. One problem when trying to design an adapter is the flange distance. These CCTV zoom lenses make it where you can be off a little and still be able to focus. The 5-50mm cctv lens is also around $25 and can be used with the original shell if you print herr_zatacke’s eyeball mod on Thingiverse and have the ability to heat set threaded inserts.

@devanopolis thanks a lot for the details! I‘ll check out CCTV lenses. I‘d love to see my GameBoy Camera get this upgrade after adding the PicNRec cartridge.