My best guest for your piece would be a Fowler maybe french like the one below close but not quite.The one below is another kit deal put together & I can't find a side view of the real deal.So...
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Timekiller said:Sorry had a Ribeye on the grill & some things come first.![]()

NOLA_Ken said:It looks similar to the kind of sideplate you'd see on a French trade musket from the mid 1700's. I'll poke around a bit more later and see if I can find anything to match it.