I've done a little research but have reached no conclusions.
It is marked: top of barrel HARRINGTON & RICHARDSON ARMS CO, ---WORCHESTER , MASS, U.S.A.---
On left frame: MARK VI and ONE INCH. The serial No. on front of grip frame is 12172. The SN on left barrel flange (with barrel open) shows a P12172. There is a S on the right side of barrel flange, and a small arrow head on the left side of frame.
No other markings. Has black H&R grips and lanyard ring.
The holster is as-new, Khaki with brass colored strap hardware, and is marked U S & O L IB 1942 (I think. Is partially faded), and has a arrowhead in a semicircle. See link to photos.
I have had this piece since 1969, and believe it to be of 1954 vintage.
The pistol appears to be unfired and appears to be near 100% in every respect.
See photobucket photos: http://s119.photobucket.com/user/colree ... y%20pistol
OOps, I forgot to add 2 photos: http://s119.photobucket.com/user/colree ... y%20pistol

If photos don't work for you, contact me at colreed1@hotmail.com and I'll send via email.
Thanks for your help.
Reed