Phil, (Conifer, CO)
Phil, I feel your pain. It’s difficult when one component holds up the whole restoration process. By your dimensions, your fuel container is probably an aftermarket tank installed by the coach manufacturer, and who knows (or can remember) which supplier actually built it. There are many aftermarket fuel tanks available; perhaps you can find one at a supplier called Transfer Flow (www.transferflow.com). They produce many fuel tanks for all kinds of vehicles. They may have one close to the size you need. The engineering, tooling and setup costs for a tank made to your specs is quite expensive. According to the people at Transfer Flow, it would be well over $1100.00 plus shipping. If it were me, I would opt for finding a replacement tank, as close in size to the original that still fits in that location on the chassis. No shop will try a repair (wisely so) because of the liability risk of welding on or near a gasoline container.