Regarding modern gumwalls, I'm a fan of the Panaracer Paselas but prefer the tread pattern they used to come with.
Anyway, I also have some high quality 27 inch tires that I don't see myself using as I prefer a bit more cushioning these days. 4 new in box, Avocet 27x7/8 - US$20 each + shipping (from Australia). According to Harris Cyclery "these are the finest high performance tires ever made in the 27 inch size. The FasGrip slick was introduced just as the 700c size started to eclipse 27 inch." I can't confirm or deny this. Anyway, they don't make 'em any more.
Jeff Wybrow
Melbourne, VIC, Australia