The Tundra Lite website says the 8” version with a stinger socket for a Just SuperSTOL weighs 5# 14oz. I don’t imagine the leaf spring version would be more than a few ounces different; possibly less since the stinger socket is steel. The site also has a photo of a leaf spring version (presumably the 10”) on a scale showing 7# 1-1/8oz.
The text describes the 8” tire as “tubeless,” and a couple of the photos show a Schrader valve stem. The wheels look custom turned to me. Definitely not like any of the three tail wheels in my possession.
There’s an exploded diagram of the Baby Bush Wheel on page 2 of the installation instructions on Airframes Alaska’s website. Below that diagram it says, “ABI-3200B Complete Assembly weight: 12lbs.” That’s an 11” tire.