Custom Rubber seals?

I'm Looking for someone who supply's ''H'' shaped rubber seals in a custom size, or do any of you guys know how to create this seal or able to make it for me like this?



I need about 4 M in length its for the window apertures on the dolphin build (and some left over), i can find H shaped seals easy enough but there all designed for car windows so are very over size for my needs, i did a small diagram if anyone here knows where i can get or can make this?

Happy enough to pay w/e (if you can make it) i really didn't want to make full blown window rims outta brass, this seams a more logical approach.

Thanks RR

RR,
On your drawing the bottom rubber would only be 0.5mm thick each side, this would allow the rubber to fall out of the aperture.

Bob