If you make the dies, its not too bad. Foundry cost for a short run of pieces they might have to fool around with would likely be an issue. If the waxes don't pull cleanly from the die, the die might have to be redone. In the US there is a business, The Rifle Shoppe, that specializes in castings for antique gun parts. They might be an option. I've been thinking about how a die could be arranged, and it could be a bit complicated. I wonder how big the market would be for a reproduction part, and what folks would pay for one. Until the die is made, and parts cast, there is no way of knowing if the project is a waste of time or not.