Ask HN: How can your SaaS startup accept (US) checks?

We have a customer who insists to pay per check instead of credit card or Paypal. We aren't US based so I'm wondering if there is any payment provider or service that would allow us to get the money. The dollar value (yearly subscription) is large enough to go the extra mile for that customer. It's even fine if the money ends up in escrow for a couple of months (check clearing takes a while, doesn't it?).