brush pile weather stripping for Slider

Hello,
I have a VIKING brand slider, approx 30yo, and noticed the brush pile weather stripping (maybe also referred to as fuzzy pile, mohair, fin-seal?) where the door meets the jam is missing and I'm getting a draft. There is an empty slot where it should be. The empty slot is on the sliding piece, on the side that meets the wall, same side as handle, on exterior of door. I see many width/depth options, is there a typical I should start with? I would need approx 8' of length (length could easily be cut to fit). Hoping backing is semi flexible so I can 'jam' it through the front of t-slot, as I wont have access to opening without removing door.
*Below are rough measurements at best, would defer to typically over exact match as im not confident in my exact fine measurements... Approx width of slot opening is approx 3/16", and I believe the "hidden" part of the 'T-slot' may open another 1/16 on each side for total width of slot approx. 5/16" (though guessing 1/4" width easier to 'jam' though front of t-slot)? I don't know how to measure would be pile height, even as approx...