The 264 was a working name for the Commodore Plus/4. There are some early models in existence where the label said "264".
Aside from a very early prototype with differently shaped RETURN key and lacking any printed text on the Shift/Lock key as shown by Marc-Jano Knopp, the 264 keyboard looks quite similar to the one used for the officialy marketed Plus/4. During the 264 phase, several different software packages have been candidated to be included in the ROM before the 3+1 software has been eventually chosen as very last choice close to the official release (LOGO, Pilot, Superscript, Easycalc, COM264, Financial Advisor). Rob Clarke has found, acquired and slightly cleaned/fixed a 264 model with Micro Illustrator as included ROM package.
Bil Herd confirmed he's been who wrote "SAMPLE" on the back of the keyboard's plate.
Rob Clarke's Commodore 264 Rear
Rob Clarke's Commodore 264 Micro Illustrator ROM
Rob Clarke's Commodore 264 has a ROM version of Micro Illustrator installed as dedicated ROM, instead of the 3+1 software package.
Michael Tomczyk's Commodore 264
On Saturday 2019-10-05, VIC20's creator Michael Tomczyk has posted some pictures of his Commodore 264 prototype and preliminary manuals, asking for an evaluation, eventually looking forward to sell it.
