As a CW reenactor who has "defarbed" a few reproduction P53 Enfields, I recommend the following resources. I don't have current contact info handy, so you may have to do some of the research on the net for contacts.
1) Geoff Walden is THE man on Enfields. He wrote a monograph on authenticizing the Enfields, and it is chock full of information on exactly what you are looking for. The only e-mail address I can find (possibly outdated)for him is: firstname.lastname@example.org If you cannot find the book anywhere, shoot me an e-mail and I will try to look up your markings ( I gots the book!)
2) Lodgewood manufacturing (http://www.lodgewood.com/) They are very helpful answering questions about Enfield markings, and have done extensive research to help people like me get correct markings on our repros.
3) also try these links:
John Zimmerman http://www.edsmart.com/jz/index.htm#about
I hope this helps,
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