Looking at your pics, Dave, your No 2 has the E in a D I ** but is not an FTR...It does have the British export firing proofs (the 3.7 Tons, .707" ? , .38, and a stylized "S" I think)...The ESC 320 is vaguely familiar...but I don't recall what it means...
(Heh...I like the itty bitty screw in the front sight blade)...
Occasionally you see these with a brass [sometimes steel] disc in the right grip panel...With or without markings...they were for unit identification...Unit designations stamped into the disc...Sometimes if you have a blank disc, it has been turned over to hide the unit markings...or completely removed to prevent your unit being known...Most times just a blank disc, as the FTR re-issues would be...
(Pic of a disc on the FTR'd GB No 2 below)
(It has the rounded front sight blade)
Dave, you have a cool little revolver...