I can see having a 55 gal tank in the garage, but schlepping a single full barrel of fuel around seems iffy.

If 5x7 is a pain due to the frequency and hassle factor, why not try for 4 or 5 x 15? You're doubling capacity for the same work but keeping flexibility.

Have you called the Barrel Guy from the Express-News classifieds? I think they have the same sort of assortment.

http://www.arizonabarrels.com/15_gallon_closed_top_barrels_drums.html