I can tell you that no MA dealer can transfer a glock 43x to you unless you are LEO. BUT they can transfer to you a g43x frame (if they know how to do it correctly and right now I mostly know of dealers doing it incorrectly).
So the real question to ask dealers is will they transfer a g43x frame for you that will be delivered by a NH resident. Have the seller just hand you the unregulated slide. Only use a FFL for the frame.