I have 1988 4x4 Toyota Pickup. The rubber seals in the door have hardened. this is causing the window to stick and will not go up/down. Where can i buy new ones to replace them?

Dealership may still have them, might try rockauto,com, jcwhiteny.com, then go to used through wrecking online or local. Might also try a local bodyshop and see if they could point you in the right direction.

It would be nice if a company like LMC trucks would put out an import line of truck products.

Until you find replacement rubber, try lubing up the channel, otherwise you could end up stripping the window crank gears. I wouldn't use a automotive type of lube due to the smell, hand lotion or a vegetable oil based cooking spray should work and not create any noxious fumes.