All About Pocket Knives

Here's the Newbie again... already. I just picked up a (another) Barlow and I'm looking for some information. The seller said this was an "original" Old Cutler and from looking at it I take that to mean maybe one of the first made. It has smooth, white delrin handles and a solid brass bolster. Also brass liners. The main blade is stamped OLD CUTLER over USA and the smaller blade is stamped patent over 3,317,996. I know I haven't seen a great many, but it's the first I've seen with smooth, white delrin handles. It doesn't appear to have been used but is showing it's age with dark spots, etc. Anybody know when this was made or any other pertinent info? (Sorry, not able to post any pics at this time.)

Thanks for your time and consideration.

Old Cutler is a stamp used by Colonial from 1977 - present.

I made a post in my blog regarding this knife and I posted the years of production from
1978 to 1986. Can't remember the source of info at this time.....

Thank you, Greg and Scott. I appreciate your input. I'm sure I'll have more questions along the way and it's good to know that there are other people with like interests in these great old knives. Take care.