Pella Double Hung Window Weatherstripping replacement material

1/4" x 1/4" foam sq with white plastic film(?)covering. The wood slot is 1/4" wide to accept with foam piece. The slot is 33 7/8" wide (actual tape measure of bottom of wood frame). The foam piece is also lightly glued in the slot. I need to replace the weatherstripping in 5 identical windows. In the picture, I taped the foam to the wood frame right above the receiving slot This is the top window of the double hung. The slot is cut in the bottom frame to met up with the bottom window where the window latch is when you lock the window. Hope you can help me purchase this item. Thanks

Here is the photo you requested (No that is not a cigarette !!!) 1/4" x 1/4" w/ a plastic (?) film (?) on 3 sides Hope this helps
Sorry for the delay but I am not that computer literate and I have to call my son for instructions on how to get a picture from my camera to my computer to you
When I went to school we used a hammer, chisel, and stone to communicate !!!
Thanks, again

Checking to see if the Handy Person from Chicago ever located a source for the 1/4" square seal material?  I am looking for the same weatherstripping that goes bereeen the upper and lower double hung window sashes.