Back Strips Need help ...info

Does anybody know where I can order the back strips for glass lids ?
Everything that I can seem to find is not wide enough.

I have a 150 gal and I tried to order a back strip from Premium Pet supply. The length was perfect but the width would have left me with a 1/4 ish gap.
I seem to need around 2 1/2 inch wide. Glass Cages used to sell it but it does not seem that they do anymore.

Any suggestions ?
Thx
Brad

Plexiglas maybe ?

Whenever I need some flat plastic, like to glue to back strips, I use a strip from vinyl siding that is being thrown away. It's just PVC (like is used for water pipes) and pretty easy to cut with a utility knife and a straight edge or with tin snips. Just a small amount of silicone cement would work. Plexiglas is OK for a small span like your quarter inch but it seems to me that it has enough weight to cause it to sag on much wider or longer applications and is a bit harder to cut.