That is a beautiful pistol, Rolf. I would put the date of manufacture a little earlier than 1700 based on style alone. It's in the French taste and follows much of the Thuraine et Le Hollandois style. This went out of favor in France by 1660-1670. It may have hung on in other parts of Europe a little longer, but not until 1700 in my view. "Master French Gunsmiths" by Stephen Grancasy shows design prints documenting this style. Also Torstn Lenk's "The Flintlock" is a great source for learning more about this and other 17th century French gunmaking styles. Am I reading correctly that you are suggesting the same man, Ian Brucker, made this pistol and a percussion pistol? This isn't possible.
As to your question.... I would plan on having to make these parts. You may find something that is close, but it will likely not be exactly as you need.