Thanks for all the tips folks, I ended up going for Rodinal as it comes in a really small bottle and is cheap. I'm glad I opened this thread because I wasn't thinking of the non-Kodak / non-Ilford options at all until 6x6TLL mentioned it.

This community is great! Over many years I've asked lots of dumb questions but there's always multiple people around who are patient enough to answer them. Thanks and stay safe