leather equipment is quite cheap in AH, i'd just buy it there, farm crystals for a stack of fire or wind, and you've basically got enough gil for the entire seeable leather set
I went to try and buy this from Deegis in the Bastok mines at location H-6 and he didn't sell any leather armor. Why I have no clue, leather was a common armor in all the final fantasy games I believe, so I have no idea why its listed here as being sold by merchants when its not. The only solution I could come up with is its a mistake, or they do sell armor in limited quantites and REAL high levels like to buy them all out and then sell them at jacked up prices cause I could see greedy players doing that. Can someone tell me if this is true? Does any merchant sell leather armor?
As said in many various other posts. The items sold depend on a few things, your rank/fame and what nation controls what region. That would certainly change things on what is sold and what is not sold, hope that helps.