Bad Gambler,
I wouldn't worry too much about that. These rifles like the Lee Enfield breed were made in very stressful wartime conditions in the main, and it is known and possible that those charged with this unique work, didn't always mark their products right. Of course many years later here we are giving relevance to sectioned numbers and the period they were manufactured, not so in many cases. So in short enjoy the rifle and I hope it sells well for you.