Price of a rapier in the 17th century

[corrado26]

A friend of mine is currently preparing a lecture on the true d'Artagnan and is also doing a currency comparison (livres to euros).
In the course of this he was able to research that as a lieutenant captain he is said to have received a salary of 900 (?) livres a month.
At the beginning of his career, however, it was said that he only had about 90 livres. (Exchange rate: 1684 corresponds to 1 livres approximately 15 euros).
Average wage of a worker under Ludwig XIV: 19 livres per month.
The searches are very difficult as there is little data to be found, if any, mostly in French and difficult to find.
Since the musketeers had to arrange their own armament, he would be interested to know how much a rapier might have cost in the 17th century.