Wiper pivot seal fabrication?

All you '63 and later guys and gals are lucky. When your pivot seals spring a leak, all ya gotta do is call Schumacher for a rebuild kit. (And then bust your knuckles installing it.)

Problem: Can't find anyone with the old (round, according to the manual's picture) seals which would probably fit the '60-"62 Valiant/Lancer. Has anyone had success finding seals or fabricating new ones? If so, what base material did you use, and where did you obtain it?

_Dan