Amazon is the exclusive retailer. It sells out often and Amazon has been very bad about putting it back in stock, so if you're interested in one, waiting can be frustrating.

You'll also need to buy the torch and propane canisters.

(Amazon recommends the tall skinny canisters, but that's not safe. Get the squatter, coleman canisters)

On top of the Amazon answer, I think you're sometimes able to get it off of Modernist Pantry [1].

[1] https://www.modernistpantry.com/booker-and-dax-searzall.html

The Searzall is on Amazon[0] and as mentioned you'll need a torch like this[1]! It's actually in stock right now so if you want one within the net 6 months I recommend buying it. They sell out quickly and they're manufactured in laggy batches. You'll also need to buy some of the propane locally. Their challenges with Amazon comes up regularly on their podcast... apparently it's been lots of headaches.

0- https://amzn.to/2MQOZzb

1- https://amzn.to/2DW7lvU