The Supreme Court said Obamacare is constitutional. But they also said it is legal to not buy Obamacare as long as you pay the tax for not buying it!
But you cant get coverage in the United States, because it is illegal for a US insurance company to offer coverage that does not conform, and it is illegal in most US states for anybody to advertise or sell coverage that is provided by a company not licensed in that state.
For most people who have some money, this means you have to buy Obamacare and pay the high prices, because you cannot take the risk of being without coverage at all. Also, since the price is set when your back is against the wall (usually) in an emergency, medical establishments jack up the prices tenfold or more for people without insurance. So, if you "self insure", you wind up paying ten or more times what you would have to if you did have coverage.
A way around this is to have somebody who knows the medical business negotiate prices for you beforehand. You then get the price control function supposedly performed by health insurance, without also getting the risk spreading function. Since it is still legal to buy insurance coverage for specific risks (like cancer, it is called dread risk insurance) you can spread your risk on those if you want to. Young people might want to get accident coverage plus a medical payment service. Older people might want to get cancer coverage plus the medical payment service. Emergency services are still available to you - after all that is the rationale for the tax.
Medical payment services dont exist yet. Lets hope there are enterprising souls who are willing to set some up.