You can find out the production date by calling Colt.
They will give you a date over the phone, but NO other information.
The Anaconda isn't rare, but prices have been skyrocketing recently.
Production of it and the Python have been suspended for the last year while new production machinery was installed.
Production on both is slated to resume early next year.
There are scope mounts that do not require drilling and tapping the Anaconda.
B-Square makes one that uses the barrel vents to lock onto.
You can get this from Brownell's.
http://www.brownells.com
B-Square Revolver Mount. #122-125-300 Colt Stainless Mount. $70.00.
There are probably other no drill-no tap mounts. Ask Brownell's, they'll know what's available.