Well, if $25-$30 bucks won't break the bank, I'd probably go ahead and replace it.
While you're at it, might want to take the inner panel off the rear door, peel the plastic up and inspect for corrosion / rust /moisture.
I see we're in the same part of the country and imagine mine started dry rotting a while back and is the culprit behind some tailgate rust I dealt with last fall. Water seeps down between the window and that bad seal into the inside of the rear door. Rust coming from the inside out is no fun. By the time you see it, it's too late.