I have a Rock River Arms Side Mount Sling Swivel For Sale. It is a take off from a used gun that I recently purchased. It is in excellent, like new, condition. This unit can mount on the left side (for righty) or the right side (for lefty).
RRA sells these on there site as follows:AR0161 Side Mount Sling Swivel - $27.00 plus shipping.
Here is a photo of one from the RRA site:
Price is $25.00 Shipped! SOLD!
USPS Money Order or Discreet PayPal (Add 4% to cover their fees!)
Please post an "I'll take it!" here, then follow up with an e-mail.