The Peacekeeper is matte finish Trooper Mk V. It was introduced in the mid-'80s around the same time that Colt introduced other economy grade handguns like the Agent (based on the Cobra), Commando (based on the Detective Special), and the matte Officers ACP. The Trooper Mk V and Peacekeeper didn't last long after Colt introduced King Cobra, roughly the same frame and action with a full underlug barrel.
FWIW: The only Mk V variant which might demand collector pricing are the limited production Boa. The Boa were Mk V frames fitted with a Python barrel, finished in Royal Blue, and given a seperate serial number run from BOA1 to BOA1200.
BTW: When someone mentions problems with Colt Troopers, it is important to note the vintage. The earliest models were the E-frame with the firing pin attached to the hammer. The rest of the lockwork was shared with their younger and more handsome stable-mate, the I-frame Python. Late production E-frames were equipped with the Python's frame-mounted firing pin.
The J-frame Mk III had a simplified lockwork powered by coiled springs instead of the V-springs of the E-frames. The idea was to simplify construction and reduce costs. The Mk V shortened the hammer throw, altered the grip frame, and introduced a few other improvements over the Mk III design.