Shipping fuel is the enemy of affordable fuel for all model aviation internal combustion engines and their disciplines. HAZMAT charges easily double the price of fuel and make it prohibitive to purchase let alone for a hobby store to provide.
What is the answer? Well Ken DuFour and I have bought fuel in bulk; 50 to 60 gallons at a time and got the club discount, or made our own by finding a store that supplies Methanol in bulk (5 gallon cans) and then mixing our own to copy GMA 10/22. So we obtain Nitro, Klotz Technoplate synthetic, and Bakers Castor separately and then reuse VPI Steel 1 gallon cans and then first decant into the can 12 oz each of Klotz, Baker's Castor, and then Nitro to come close the GMA 10/22. Once the additives are in the can, we then decant with a cannula the Methanol until the can is full. Close enough. We have compared it in our stunt engines with GMA 10/22 and can find no difference.
We avoid the cost of shipping HAZMAT charges and we keep the cost to about $25.00 a gallon.
Where can you get the ingredients? Well, off road race shops, motorcycle race shops, Go-Kart shops, or Top Fuel Dragster shops are some of the places to go.