Hi Geoff,
You actually have a lot of options. For your purposes, 17th century French, Dutch, or English locks would be appropriate. The single best selection that includes all of those is The Rifle Shoppe (
www.therifleshoppe.com). Unfortunately, they take forever to complete orders and are very frustrating with respect to customer service. Nonetheless, they produce pretty good cast parts. If you are willing to wait 1-1.5 years for parts, they are probably your best bet. At least get their catalog. If they have parts in stock, they may fill orders in less than a month. E. J. Blackley and Son (
www.blackleyandson.com) in England has excellent parts sets for English doglocks. They are generally faster than TRS and the quality of the castings is higher. Leonard Day in Mass. makes some fine 17th century locks but they are mostly English type 1 and 2 locks (see Brian Godwin) and later doglocks. The Rifle Shoppe has the largest selection of appropriate locks and deserves a first look. Keep in mind, they mostly sell castings that you build into a lock. You can buy many of their locks assembled but they are very expensive. Below are photos of an early English fowler that I built from TRS parts. The lock is an early (1640s) type 1 English lock and the stock is loosely based on the Forbes fowler, which is one of the earliest extant firearms brought to New England. The lock is a copy of one recovered from a dig at the site of a blockhouse in Rhode Island destroyed during King Phillip's War (1675-1676). I am going to replace the ramrod tip , which is totally inappropriate for the gun (what was I thinking?).
dave