Mirco Tools, look em up on the web, sells an assorted pack of self stick light baffle (get the USA made for better density) for $20. You cut the strips with a razor. Pick out ALL of the old goo, stick in the new and you have enough left over to start a business. Those kits aren't self stick so you will have to use some contact cement and that is a mess to deal with.

BTW you don't need camera specific foam, you need strips of the correct thickness and lengths.