Is there an email privider that lets you block ALL emails NOT from the USA?

[camosilver311]

I sell cars on craigslist and am getting sick and tired of weeding through all the spammers who respond to my ads. They ask a normal question to get an initial response from you and then come back with some stupid story to get you to click on a link they send you. It's frustrating and a waste of my time. I traced the IP of the last email to brazil, I don't know about the other emails but many of these scammers come from other countries.

I was wondering if there is an email provider out there that allows you to block all non-usa ip addresses. This would solve the vast majority of my problems with spammers. Or, even, better, if there is a way to do it with my gmail account.