I’ve seen come up for sale occasionally "USMC" marked slings that are marketed as Reising slings. In fact, there are a couple on eBay right now. Most genuine Reising slings I’ve seen are unmarked. The same seller that is selling the USMC slings is also selling Reising slings marked "F. S. Co.", the Carbine Club had an article written up about the FS slings in CCNL 236 & 237 where they state the FS slings are non-original and reproduction (FS for fake sling).
I’m wondering, are the USMC marked slings genuine, or are they from the same bag as the FS slings?