I saw MGM087x some time ago. It was a 4-screw 6.5-inch M29-10 like yours. Unlike yours, however, it was in a plain jane 1st gen blue plastic box. Label said the ship date as February 21, 2006, and the product code was 161240.
A couple of quesitons.....
Do these guns have the ball-detent lock-up mechanism on the yoke?
Is it possible to take a close-up in-focus picture of the gold emblem?