You've made a statement and put a question mark at the end. You have not asked a question.
Yes, one gun manufacturer at least built a two barrel derringer that was chambered for 410 rounds. While a 410 is relatively small, technically is is still a shotgun, and in a pistol as small as the derringer, firing it is a wrist-breaker.
The one designed and made by the manufacturer
Never heard of it. Need a detalied description of all markings, finish, barrel length, condition. Leinad made several different models of .410/45LC derringers. A five shot pepperbox, single shot pistols, double barrel pistols, and a Model PD which was a two shot revolving pistol.
Colt has never made a 45/410 pistol
If this is a Stevens single shot #35 in .410. It is on the Federal List of banned weapons and is illegal to possess, or sell. Look at the National Firearms Act.
Iver Johnson made some Westernfield matte rib 410's
Depends on the laws where you are.
I believe the Thompson Contender could be found in .410. There was a company from Argentina which manufactured a single shot pistol which, by replacing the choke, could fire either a .45 Long Colt round or .410 shotgun shell. As far as I know, they're no longer in business, and you'd have to search for one which was for sale.. offhand, I'd recommend Gun Broker, Auction Arms, and Guns America. You'd have to buy it there, and have it shipped to an FFL for receiving.
Depends on whether it is an NFA item or a C&R
In their catalog
Local gun shop, local gun show, for sale ads, Shotgun News, Gun List will get you started.