Advice for tinting rear window

[mchyphy]

Alright so I've got a 72 Cheyenne with the sliding rear window. I want to get it tinted, but after calling a tint shop they said they wouldn't do the rear window without charging an arm and a leg to do it right, as they say that because they can't get the tint to go over each window entirely, dust and dirt will end up under the tint, messing it up and causing it to peel. They suggested either having it replaced with a solid window which would be cheaper, but I like the sliding window so I want to keep it, or looking for pre-tinted windows, which I have almost no idea where I can find that. Anyone go through this before and think they could help me out or give me some advice? Thanks.