Great Dutch pistol from 1680's-1690's I suspect. Her lock plate and side plate are the biggest tell's. Here is one with a similar lock plate profile from Herman Historica http://www.hermann-historica.de/db2_en/onlinekatalogeneu/schusswaffenneu.html and search for #2080
It is possible the lock could be earlier as I have found comparable examples in my Dutch firearms book by Arne Hoff from the 1660's
