vkykam has posted EXCELLENT directions on how to replace the door power window regulator "clips" in the past. The part number for the clip (or SLEEV LOCK REG as Subaru describes) it has, I believe, been short a digit.
Try Part Number 62101PA081 for $9.99 (that's here in NO SALES TAX LAND)!
It is an easy fix, but I could only find one screw to remove in the area where the door latch is...
Cheers!