If it was me I would make it work for the winter and get a new heating system during spring. You can patch up the tank with JB weld or other preferred method. Make sure the tank vent is clear of any obstruction and do a daily check on the tank. The tank is not pressurized so the biggest hazard is leakage and possibly fumes. When spring comes you can use states incentives to get heat pumps installed and see options for secondary heating system. When it comes to fuel I would call around there is always some one who would deliver and worse comes to worse get some diesel from the gas station, essentially the same as heating fuel.