Direct from their website. Had them shipped to the hotel I was staying at in Arizona and installed them at the range. I needed to speak to Mr. Dawson himself on the phone before they would do that, as he doesn't like sending his sights to a different shipping address from a billing address (lucky, I also happen to have a US CC or it might have been cancelled completely if I had used my Canadian CC, judging by his tone).
You may want to order them from Brownel's instead. But, having said that, they are a high quality product and I'm very happy with them.