Proofhouse should be able to help with year. These have increased in value over the past two years or so. If you check Gunbroker for closed sales, you should get a good idea of current value. FWIW I think they are neat guns and have always wanted one.
Wow. In the "Old school Cobra" thread a little ways below your thread here I mentioned I never seen a forum member with one of these that I remember and here you post one. I like the business like look of these. I always have
I like the looks of the "Parkerized Agent". It has the same appeal as my 4 in Peacekeeper 357 Mag. It has the Black Matte Strike Finish,not preety but very functional. This finish is all about buisness..
Your gun dates to 1982. The 3rd edition of The Book of Colt of colt Firearms has an index with the later serial numbers. A lot of people think these were made during the UAW strike due to the lack of polishing, but the gun was actually introduced in 1982, three years before Colt's workers went on strike.
Here's a copy of an ad from 1982. I like the way they refer to it as a "combat finish".