I have the remains of a Beseler printmaker 35 in my attic - they're so-so "beginner" enlargers, probably just fine for 8x10 prints, but they're kind of rickety and cheap, lots of stamped steel (and the "Cadet" is even lower-end). If you want a more sturdy enlarger that can also do medium format, the 67C is a much much better machine. Single column though (vs. a frame) so it's a bit more compact and can be shipped reasonably. The column is thick and sturdy extruded aluminum. They're very common with condenser and color heads. There were (I believe) 2 models of color head though - the earlier one requires and external power transformer and seems to be one of those "when it's dead, it's dead for good" things; the newer head plugs right into the wall. As mentioned by Paul, the 23C is a good machine if you can find a clean one - they're very common, and were the standard school enlarger and were built to take some abuse. they're much bigger though, since they use a ladder frame vs. a single post.
Beseler did make a 6x7 conversion kit for the Printmaker, they're rare and expensive and seems kinda silly unless you really need the smallest possible MF enlarger and won't print very big.