Keep in mind Apple was still making SEs in early 1991, despite having "discontinued" the model in October 1990. I've seen more than a few from early 1991, all of the SuperDrive variety (as opposed to the FDHD badge).

I know some markets also had certain models for longer periods of time. The LCII was discontinued in February 1993 in the States, but it was possible to still buy them in overseas markets. I think they were in either a British or Australian catalog as late as Fall 1993. (If someone from either country could confirm that, please do!)