It is not what you have asked for, but it might help: a 40mm f2 Minolta Rokkor (originally for the M-mount Minolta CLE) is an excellent very sharp lens that usually goes for about 250 USD, and the 90mm f4 Elmar-C might be a bit slow, but it is very small and light and an excellent lens as well that also goes for about 250 USD. You won't be disappointed with either of them.