Serial # can tell you when it was produced. (www.proofhouse.com)
For value, check comparable items on gunsamerica, guns international etc.
I have an Army Special in 38 Special (see below). Had Colt rebuild and reblue it a few years ago. Looks and shoots like new. The action in those older Colts was hand built and pretty close to the smooth Python actions.
Now that Glenncal1 mentions it, I recall buying a set of after market target grips and they do fit my Army Special. I'd have to look and see the brand and frame designation. My mobility isn't the best right now.
I took the liberty of displaying below the pic you cited.
Don't want to take someone's thread over, but while you're talking about Colt grips, I have two sets of grips, they are plastic or some such material. Both are the same size, fairly large, with a simple diamond inside the pressed checkering pattern.
One has a right hand thumb rest, and both are in boxes from Herrett's Shooting Stars-Genuine Walnut Handgun Stocks- Herrett's handgun Stocks, Twin Falls, Idaho.