help identify Enfield revolver

[GerryLE]

I bought an Enfield revolver that is registered as an Enfield No.2 Mk1. I can't find any Enfield markings or a serial number, although there is one on the registration cert. On the cylinder is ESC.321. On the right side of the frame is what looks like an E combined with a D, I*. The DE stamp is also on the top strap. under the barrel, a proof mark over NP then .38 767" 3.5Teovs. on top of the barrel is 41 (year of manufacture?) and som other printing that I can't make out.
What do I have?

 

[tiriaq]

E combined with D is the Enfield mark. I* is the model.
Absence of serial number is most unusual.