Interested in understanding if non US citizens (above 60 years old) can buy health insurance in the US; if so, what are the options & where to find these plans.
You can buy insurance directly from a carrier, as a non-citizen. You cannot go to the insurance exchange, since that is available only to citizens. The plan offered to you will be “off exchange” — it will match the plans offered to citizens, but will not give you any subsidies to pay for it.
If you are web savvy, you can find out which carriers serve your area and shop on their websites. If I were you, I would find an insurance agent. He or she can help you address any unique issues, such as regular travel back to your home country.