The 666 12 string was introduced back before the 'number of the beast' was such a big deal in the public's mind. Nowadays, it's kind of the kiss of death for your item to give it a model number starting with or containing '666,' much less have it be the entire number... well, unless it's a Megadeath album or something...
Anyhoo, it's odd that a 12-string guitar would
get all 6's for its name anyway. It briefly became the 1225 when Sears unleashed
the '12' prefixes in F/W '68, and then became the 1226 in F/W'69, and
the 1227 in the spring of '70, at which time it also gained the 'space dot' logo
on the headstock, and a funky pickguard.
Spring/Summer 1968 at $46.95
as the 57K666L
My last available listing:
Spring/Summer 1971 at $49.95
as the 57A1227L