I bought mine through the USMC Scout Sniper Association, believe they set asside 200 or 250 with SSAxxxx serial number for the active members.
As I am member believe I paid just over $1k at the time and mounted an early original green Redfield. I have since picked up a green Leopould commemorative and one of the Iron Site reconditioned Redfields (a couple years ago). They are a great looking commemorative, and are great tack drivers. Although there are more modern weapons that are more accurate, I like Wood & Steel. As has been said the standard USMC ones come up on GB pretty regularly, I am sure Remington cranked a couple thousand out, but havent seen an SSA marked one in a while. Skid