I need a long life accelerator pump gasket. My hollies keeps cracking with normal arm travel. It dries out from sitting, as its more a full scale model car.

Not sure about alternatives (I always use the black ones) but coating them with vaseline might help a lot....

I had the same problems.it seems the ethanol in the gas is nice to them.I since have switched to the green pumps.they are for alcohal.twice the money. but worth it.been good for years now.before that the winter storage was too long.leaked every spring.

I would go with the green diaphragm material mentioned. All the recent Holly rebuild kits that I've seen have the the green ones.