My #35 is as yours and too, my bit of Hans Tascher #5 Catalog, N.Y. the same illustrations. My Obie Model M bearing it is one from the first month of the first year of Mauser production, Dec. '13; SN in 78K I believe it was a Tascher import.
You may be thinking of the Lyman Model 36 for the Mannlicher. The diopter arm swings gate-like to accommodate the bolt travel. Pix of one below on a Model 1952 in 7x57. At about $500, the sight now values at more than I paid for the rifle... in the dark ages!
From the prior blog re sight hoods. I've seen a few Obies offered with hoods. Some postwar made FN commercial '98 rifles are yet with hoods and that patter will supposedly fit the prewar Oberndorfs. The style is of the compounded-contour hood with the uppermost portion of smaller diameter. Frosty has such pattern shown in his pix offering.
I suspect they may have been made by Oberndorf, but 'if' furnished, more often as accessories. They don't survive for the same reason most don't on the high power bolt rifles; not popular! All pre '64 Model 70 rifles came with them, few survive on the rifles!
Bit of trivia, my type M of 1923 in '06, SN is shown below.
Is yours 87505? Mine as yours, but original sights.