Nope, I had not seen those. I bet they sell at a premium, though, and as I said unless it's been sitting on a shelf a long time, the carb kit you're likely to get today will have the same ethanol-resistant parts in it. Maybe the Daytona kits are better. My guess, though, is that they're not a manufacturer and are just sourcing their parts from existing supply chains already in use by Standard, Holley, and BWD among others.
When getting parts for the fuel system for the Imperial, I made sure everything was rated for E85. Worst-case scenario, I could run on it... or best-case scenario, I guess, with a little reprogramming of the fuel/spark tables and a toggle switch to jog between settings. E85 is great for power, especially with forced induction. That is, if you don't mind how fast your engine has to drink it to do so. To run it with a carb, you're looking at a complete change of carb & distributor tune, including much-richer jetting and a much-more aggressive spark curve and total advance.