Hi Ed
First of all, my congratulations. What a wonderful addition to a collection.
Your proposal would certainly make for an interesting project.
LOCK: I have searched my sources for replica locks. The earliest available snapping style matchlock lock available commercially is from about 1544. And it's English. So that won't due. The German/Bavarian locks are all late 16th to early 17th Century. And that won't work either.
There are custom lock makers that can make you an exact copy of the one in the photo above. And that lock looks correct to me for this extra early period.
Unlike a flintlock, this style of early matchlock would be fairly easy to build for a custom lock maker. So I would suspect the cost to be reasonable. If you have basic measurements along with the photo(s), it's even easier. Should you decide to go this route, let me know. I have 3/4 sources.
Meantime, check out this Thread from another Forum member. In that Thread there is a Link to another Forum. This member reproduced a copy of a snaplock from one in Michael's original collection. I'll send Richard an email to lend his comments on your Thread. I'm sure he would also like to see this barrel. Do you have any other photos ?
http://www.vikingsword.com/vb/showthread.php?t=23238
Rick