That's easy. If you don't want to mess with the module system, then open that module's item_kinds1. Hit Ctrl+F(search function) and search fpr military pick. If you find that entry, then simply replace it with the one from Native(that one you posted right there). If you can't find it(be VERY sure though), then add the entry to the bottom of the file, above the very last entry(tableu round shield or sth) and then go to the very top of the file, where you will see a number(in Native is 603, but in mods it may vary, it depends) and add +1 to that number. If, for example it says 950, you replace it with 951. Save the file and exit, wait for a couple of days(or start a new game, if you cannot wait) and find your weapon in the stores.