i used Rustoleum flat black enamel. It works fine. The gasket's use isn't an issue here because I have weatherseal under my wood collar that serves as my freezer seal. The original gasket is between the lid and the collar which is screwed to the lid. So it really doesn't need to be there, it's just a filler. Also, it's so old that it's not flexible anyways!
I didn't want to take everything apart and replace with a black gasket also. On the inside of the keezer lid assembly with collar I have rope caulk everywhere, so nothing's leaking out. here are some pics of it finished