You could try selling on trademe.co.nz to get NZ orders. It is a lot nicer than ebay which does not have a prescence here. All photographic stuff is very expensive here and people would support you if the price was right. There is someone selling chinese 120 film to the Holga crowd on trademe. I would consider the auction sites nothing more than advertising and use them to drive traffic to a free standing site.
I use FP4 and TMY in 4x5 mostly. The only chemical I buy is fixer, powdered would make shipping easy. C41 film and chemicals would be nice.