Here is a scan from the 3rd catalog of Command Post showing the Gramps and Grizzly’s KBS Eliminator.
This catalog was published in 1987 and scanned and uploaded by former Command Post employee and airsoft enthusiast Tim Ellwood to his blog
Tim worked at the Command Post from 1986 until 1988.
Here is a link to the first batch of scans:
And here is a link to the second batch of scans:
The catalog also contains one (if not the only) picture/advertisement for the California Cobra.
(Edit: I originally wrote KBA instead of KBS)