I have a Durham Duplex (the T bar style not the comb straight thingy) on it's way to me as part of a bulk lot. I read that "carpet cutter blades" make perfectly adequate blade replacements for them (I'm not convinced, but I'll try anything). Problem is, searching comes up with all kinds of candidates. The most likely suspect is the following style:
Confirm/Deny?
Confirm/Deny?