Rin Tin Tin

Ive got the common problem people seem to have with the rear window falling down because the tracks rust out. Ive got this problem now but the dealer says the parts are discontinued for the 04 4 runner. I have a 2004 4 runner sr5, and am wondering if anyone can help direct me to a place where i can find some replacement tracks, or whatever the parts are that i need to fix this issue. There must be some aftermarket company that makes these parts. I would really appreciate some help finding these parts. Im not sure if its just the track or if there are a few other parts that are needed.