> most of the world has solved it by making ambulance (EMS) funding similar to fire...
About 65% of the more than one million firefighters in the U.S. are volunteers, with nearly 19,000 fire departments being run completely by volunteers.
A pretty large number of EMS is also volunteers. Basically wherever you have a volunteer fire department, you'll have volunteer EMS (if it's there).
St. John's Ambulance service in Australia is a hybrid of core paid positions and volunteers (varying by region and demand).
In rural Australia most of the fire, ambulance, and emergency response service are volunteer manned and (locally) run, with federal and state assistance for equipment and costs.
Costwise AU Ambulances are either free (if you're a St. John's member - cheap per annum OR if covered by private / work insurance) or (a decade out of date number) a flat fee of $500.