Suggestions for replacement light seal material in old Zeiss folder?

Hi. I have a 6.5x9cm zeiss folder which is a joy to use however the film holders/camera back are leaking light and I am looking for suitable material to replace the velvet looking strips in both parts. Should I just try to find some heavy velvet, or is there anything more suitable out there in the modern market? Many thanks for your suggestions.

velvet ribbon can be bought at a fabric shop. it has the advantage of having finished edges that won't shed.