A guy at my field uses an old beer case box, really thick cardboard) for a field box
i use an old dufflebag, carry the fuel with pump in one hand and everything else in the duffle, works great. i bought one of those plastic organizers to put tool/parts in and set the radio on top in the bag. total cost for carrying supplies maybe 2.00US
but i did buy one of those Sullivan fuel caps so i never have to unscrew the cap other than to switch bottles