I'm not sure I understand the intent...
Pistol-caliber shotshells have been available for quite some time, and (for the determined) you can get the plastic caps and reload these. They fit normal cylinder chambers, I believe. I'm not sure what advantage a .410 hull would offer.
Sabot loads usually have a specific application, such as providing rifle performance in a shotgun platform. The rifle would be better, but there are areas where rifles aren't allowed. Therefore, there is a "driver" for this application, and research is done, and a product brought to market. Where is the driver for a sabot in .45 Colt? If you want a smaller, high velocity round, just use something like a .357 Magnum.
Not trying to be a pain in the neck, but I'm just not following the concept.