OK, it appears to be a Model No. 8 - and it is a takedown. Rear sight as noted is a No 8, front is an FS22. Serial is in the mid 35,000 range.
Looking forward to taking it out to play.
Any C Broad Arrow markings? A letter "C" around an upwards pointing arrow, the Military Property mark as used for some long time.
How wide is the action? an inch, if it's a Model 8. If it's the 1 1/4 inch thick action, it may be one of the ones that the Cadet Corps had on inventory for years and years, which does not fit in the Models Listing well, but looks a lot like a shortened down Model 12.
I have one here that looks very much like that one, except this one has been drilled and tapped for (I think) a set of Redfield sights, currently blanked off with screws. Mine's Serial is mid 38000, C broad arrow stamped on the RH side front top corner of the action, as well as on the barrel just forward of the first mark. There is some signs that the forend was so stamped, and it has a brass disk inset in the RH of the stock. This one has a cocking indicator, as well as is on a 1 1/4 wide action.
I'll check it out tomorrow to see if it has the proof date letter under the forend.
I did note a very small (1/16 inch or so high) number 8 on the LH, side of the barrel, just in front of the takedown screw, and just barely above the hand guard, dunno if it has any significance, or none at all, but it appears factory applied.
Mine has the BSA No8 rear, and their small No 19 dual element sight as seen on the Model 12 page.
I am pondering whether these were a later version of the Model 8, using the same actions rather than separating them by thick and thin versions, by the time these were made. The Rifleman.org site is pretty convinced that the Model 8's ALL were made on thin actions, but ... Things that make ya go Hmmmmm.......
Ahhh... On the page for the Model 4 rifle, there is a statement to the effect that they progressed to the wider actions as used on the Model 12, through the line.
Which directly contradicts their saying that ALL the Model 8's were on slenderized up actions...