email them at firstname.lastname@example.org ask for a price. According to what I read they have a 22-30% effficiency and output another 60% out as heat. They need a temp of right around 1000C to run. they are supposed to last 20k hours, but the bearings are rated for 90k hours and should last that long provided you don't overheat them.
There is concern they aren't actually shipping a product, and no one has posted a price.
I would probably be looking at thermoelectrics they typically are in the 400-600C range although they aren't hugely efficient, they would be like supplemental in like an exhaust gas cooling loop.