Check with our Industry Partners in the Industry forums. Bravo Company and DSG Arms are two that come to mind right off the bat. They have the short bolt on rails readily available, and are good, reputable dealers to deal with.
On a seperate note, you may want to review the rules for posting in the EE. Duplicate ads are not allowed, meaning, you can not post the same item in more than one forum, i.e., Want to Trade and AR Accessories.... Just a heads up.