My experience is pertinent to your destination but very limited:
In 2015 I picked up a gastrointestinal infection. On Day 5 I caved and went to a walk-in clinic in Ljubljana. It was a big operation that felt sort of like an emergency room. The clinic took a pretty detailed medical history, did blood work (results back in an hour or so), and gave me IV fluids for dehydration and low potassium level. They referred me to a nearby gastro clinic, probably because the infection was bacterial.
The gastro guys took a more complete history and did an exam. It was agreed that further treatment wasn't necessary since by this time (several hours after I walked into the clinic) it was obvious that my symptoms were abating. Total cost for treatment at both facilities was about US $222. My insurance (BC/BS) handled the claim more or less as it would have done for similar treatment in the US, I think. There was a $20 co-pay for the doctor's visit, and part of the rest was out-of-pocket to me since I hadn't yet met my deductible for the year. Otherwise, it was fully covered.
By comparison, I went to a private physician in Lyon, France, this summer for a possible eye infection and persistent bronchitis. She spent more than 15 minutes with me, and I paid her less than US $30. I didn't bother to file for that.
For what it's worth, in your shoes I'd just buy a policy to cover evacuation. I'll bet you've got a relative who could front the money for medical costs at the European level in a pinch. Even if not, if it was a really significant amount, I think something could be worked out with the medical facility.
One tip: It's worth a phone call to your insurance company before departure to find out whether--in the event you do need treatment--you need to provide documentation in English rather than in the local language. BC/BS accepted my Slovenian invoices, but I don't think it's safe to assume that all companies would do that. The reason you want to know is that, if translation is necessary, it might well be a lot less expensive to have the work done in the country where you receive treatment. Back in 1995 my mother's insurance company required English documentation to cover her extended hospitalization in Greece. We had that done before leaving Athens.
