SnugTop Back Window Handle Leak

Has anyone had experience with a leak in the latch/handle of the back window? Water seems to come through their pretty consistently when it rains, and I am looking for ideas of how to seal it up, or find out if it needs to be replaced.

 

Adding some images, in case it is aftermarket or something! It has a mechanism which allows it to be unlocked and opened from the inside. Here it is in the unlocked position:


Here is the inside piece. Pressing the button allows it to open when it is locked.


Here is what it looks like from the outside when locked. The handle presses into the window and clicks in. Mostly I keep it unlocked, so I have not tested the seal much with it locked.