I believe these are US Armament's guns made under Colt licensing, sold exclusively through Midwest Gun Exchange and Florida Gun Exchange.
It's nice, but the price is too high- $37K+ for the unlicensed one, much more for the licensed Hartford-Horsey-logo one.
A decent, reproduction model 1862 percussion Gatling gun from Battery Gun Company with tripod will start around $5500- and includes a tripod, but only 20 reloadable chambers.
Chambers are about $600 per hundred, but no extra help for cleaning afterward is included.
I know there is a huge difference between the 1877 and the 1862 guns...but why doesn't someone come out with a $3K Gatling that still looks good? I'm more or less surprised the Italians haven't yet.