Look at CC #8, lower left on Harrison's clear overlay template. Assuming the scale is way off, which I have heard it is on this template, the CC #8 Harisson calls "Provisional acceptance mark found on post-WWII replacement stocks produced by Jamestown Lounge" is pretty near a dead ringer. The trunions may be a little more pronounced on the Harrison template but, unless my old eyes are particularly bad tonight, everything else looks pretty close.

That still doesn't account for the highwood, which makes no sense as a post-war replacement. I still don't know what it is.

I don't have a Std. Pro. but Harrison says the SP cannon breech is not rebated. True or false?