This is what the Blue Book says about it:
"TROOPER MK V -- .357 Mag. cal. only, 4, 6, or 8 in. barrel, adj. sights, walnut target grips, improved version of MK III action, vent rib barrel, a few made with solid rib, redesigned 1982. Discontinued 1986." They give approximate prices for blue and nickel finishes, so I guess those were the only finish options.
I think the "redesigned 1982" refers to the previous version, the MK III, being redesigned and renamed the MK V. The production years shown for the older Trooper MK III are 1969-83, so that fits right in with a tiny bit of overlap. They did the same redesign with the fixed-sight version of both guns, the Lawman MK III (1969-83) and Lawman MK V (1984 and 1985 only).
Colt also made a model called the Peacekeeper (made 1985-87), which is described as "...similar to Trooper MK V, 4 or 6 inch barrel, matte blue finish, rubber combat grips, adj. rear sight, about 42 oz. Mfg. 1985-87". I believe I fired one of those, many years ago, as a buddy of mine had bought one used at a gun show. If I remember correctly, it shot well, and never gave him any trouble.
Hope this was helpful.
"Placement is power" -- seen in an article by Stephen A. Camp
(RIP, Mr. Camp; you will be remembered, and missed)