The American Alpine Club does provide some rescue insurance as part of its membership. It's the only group that I know of that does. As I recall it's fairly limited.
In the United States, rescue is still mostly free. Any costs are generally covered by the local government and if you are rescued your county will likely be billed for your rescue costs. So far, most counties aren't passing those costs onto people, but there's a lot of discussion around the issue.
Evacuation via helicopter is generally paid for by your health insurance. The situation in other countries can be quite different. My understanding is that in most of Europe you will be billed for any rescue efforts done by the local rescue organization.