I landed my first job. Means I got my first job. Landed in my case means to have achieved it. Could your sentence have meant loaned me my first machine gun (Loaned = to borrow)

To "land" something, in this case, would be a form of "to provide", but with a bit of a different connotation. "My contact was able to get me my first sub-machine gun" would seem to be a good rephrasing to me, albeit more formal.