I like the saying, "you are entitled to your own opinions, but not your own facts." So what are the facts? First, to say that no P53 Enfield long rifles marked V*R were used in the US Civil war is incorrect. The royal cypher V*R stands for Victoria Regina (Queen Victoria). And virtually every single London Armoury (LA Co) marked lock plate produced during the US Civil War-era had the royal cypher whether made for commercial export or a British Government contract. LA Co produced them the same way and used the same machinery regardless of the customer. The US and CS both had contracts filled by LA Co which were marked V*R. Were those made for US/CS contracts identical to the British Government contracts? Without getting too deep into the woods, there is some evidence that those made for export to the US/CS had primarily Palmer type barrel bands vs Baddeley bands as specified for the British Government contracts. Even that distinction though is not absolute. Some with Baddeley type bands may have been imported late in the Civil War. Anecdotally, Baddeley type bands were claimed to be dug by relic hunters in Georgia. So who knows? The LA Co P53s were imported in pretty large numbers, and they were all marked V*R under the crown behind the hammer. So put that notion to rest. It is difficult to deal in absolutes about every commercial P53 Enfield because there were so many different commercial gunmakers producing them.
So let's consider this particular Enfield and what we probably have here. What I am seeing in the pictures here is a P53 type II Belgian Liege produced weapon. The British Government bought something like 150,000 from the Belgian gunmakers in Liege during the mid-1850s when the Birmingham commercial gunmakers could not supply all their needs, or what they did produce failed inspection. This type II looks like one of those. Type II's were not nearly as commonly found in the US Civil War as the later type IIIs. However, some type IIs did see US Civil War service, for example the Robbins and Lawrence produced WINDSOR marked Enfields were type IIs. Once again, difficult to deal in absolutes, but type IIs are much less often found with US Civil War use.
Is it possible that this particular Belgian P53 type II may have been sold off as surplus and shipped to the US or CS? I don't see any evidence that it was accepted into military service by either the US government or CS government. What can be said is the presence of the V+R cypher, which is how the Belgians marked it, the year in italics in front of the hammer, the British military rack and issue marks on the butt plate tangs and other storekeeper marks in the stock are usually considered as strong evidence that this particular Enfield did not see any US Civil War service.