78 NP203 oil change question

[teamssc]

I've only had this truck a few months and it runs great. I'm trying to work my way through the fluid changes and want to change the fluid in the NP203 but I can't find have gaskets to put the covers back on. Where can I find the two gaskets I need? I've found whole rebuild kits for $25 or so, which I don't mind spending, but I only need the 2 gaskets. I guess I can always drain the fluid now and do the gaskets later. With 5 qts of 10w30 just running $15 it's no big deal to do it now and later.