Old Researcher of course has saved out the auction pictures.
Robert Stack DHE 410 01.jpg
Robert Stack DHE 410 02.jpg
Robert Stack DHE 410 03.jpg
Robert Stack DHE 410 04.jpg
Robert Stack DHE 410 05.jpg
By the condition, Mr. Stack obviously wasn't out "huntin' the bottoms" with Dave Lien with this gun!!
Robert Stack's Parkers were all different grades. The .410-bore was a DHE, the 28-gauge was a BHE and the 20-gauge was a CHE. Unfortunately I don't have the serial numbers of them.