and welcome to The Firearms Forum.
Hopefully someone will be able to add more to the thread. So check back soon and often.
However, it sounds like something you would want an authority on Colt Custom guns to do an appraisal on.
The piece you are describing sounds like a Bright Stainless Steel with a Class A engraving.
Is so, the price could easily exceed $2K
Below is a link to Colts Customer Service.
Please do keep us up to date.