We can't see your complete serial number, so:
Several possibilities:
1. Extra digit added accidently or on purpose
2. Miss interpreted serial number, eg) Lxxxxx would be a BSA series serial number that someone "corrected" by adding the "0" prefix
3. A totally made up serial number
Yeah Lee Enfield I'm wondering why I get stuck with all these anomalies? Anyhow ....that's were I'm at with it, either 1 or 3.....I guess we have to leave it at that.
By the way the bolt is numbered the same way!!