Cheap alternative to seal string?

[Asazman]

I am running low on seal string and need to set up my Prometeia again, but don't want to spend $40 for some new seal string. Is there something similar to it (not foam tape or anything like that) that could be purchased from walmart/home depot/lowe's? Something in a puddy form that insulates, that's all I'm looking for.

Thanks everyone!