The Brits once (originals) made a 58 cap and ball revolver. I'd like to see the Italians run off something larger than 44.
I remember seeing an Article in an old American Rifleman about a guy who took a 38 S&W revolver and somehow converted it to cap and ball. (I have a several early 1950's issues in my library) As I recall the targets he shot were impressive. (Talk about retro-engineering, thats about all the new in-line offerings)
We already have folks making conversion cylinders for cap and ball revolvers, what about a conversion cylinder back ward to cap and ball for a modern revolver. Thats what the guy did in the 1950s with that old S&W. Some of the early and transition guns after the civil war could fire either center or rimfire versions of the same cartridge by flipping the firing pin. As I recall a few could fire even percussion or rimfire, by switching a mechanism either on the hammer or the firing pin.
It would seem it wouldn't be too difficult to retro-engineer such a system for a modern gun.
A big problem would be the difference between chamber diameter and the forcing cone into the barrel and then barrel diameter, as well as whether a soft lead bullet would just strip through the rifling.
I once approached an American reloading manufacturer about making a simple straight line loading tool in a special obsolete caliber. With me paying for the special reamers & tooling and buying a lot of 100 pieces, they still wanted over $200 a piece. At the same time for a standard caliber they only charged $22.00 wholesale for the same item. One of the guys that worked there called me a few weeks later to say he could make them after hours at home for $125 a piece. (Sounds like road apples to me)
The dollar exchange rate simply isn't right for approaching the Italians to make them for import.