The estate of famed Colt Vice Preident John Keosayian has been auctioning several pieces from his Colt collection. Ending tonight (in about 3 hours) is an auction for a a Colt Accurized rifle CR6724 which has serial number 1.
I purchased an Arms Unlimited Colt MK 12 HBAR rifle on 21 SEP 2019 at $1495 from Arms Unlimited. I picked the rifle up today (27 SEP) from my local FFL. I am in the process of gathering additional information on the rifle and will publish more details soon. Here is a photo of the rifle.