Where can I buy the health insurance for foreign visitor who will come to visit USA for three months?

Is there any website that I can check the info?
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Any guest you have staying should purchase there travel insurance in there home country. Most insurance has restriction on the nationality of the user. I travel to the states and have found that the UK travel insurance is much better value for money than what is available in the USA. $70 for six months covers and up to $10 million dollars worth of treatment with no surcharge
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