Hatch window gets stuck

My hatch window gets stuck a little under halfway if not pushed in by hand.
Is it because the bottom weather stripping is missing? Or something else?
It can move back and forth quite far when rolled down.
Also, does anyone know where I can get some black window trim pieces? The cover was ripped off.

I'm in the middle of restoring this old beast. Found it sitting behind the house of some old farmer. Paid $1.2k. Fully mechanically sound. Already fixed everything electrically wrong with it.

Damage is only cosmetic. Need some suspension work, (time for bushings.)
!YES MY LOWER BALL JOINTS HAVE BEEN REPLACED BY A TOYOTA DEALER!
I was able to put this thing on a two-post lift and look under it before buying. The frame was coated under recall the same week it came out, (got access to service records) took a ball-peen hammer and wacked just about every inch of it. No visible rust, nor structural.
A few body panels have rust, driver door and both front fenders. I'm gonna replace them.

I love this thing.