That's the second-gen "Luxus" (HW 35L) stock - semi-beavertail fore end, Monte Carlo comb, curved cheekpiece, in walnut - see catalog pic at post #27 above. The original "L" was a curvy Bayern style. The Monte Carlo 35 was also offered in beech as the "HW 35B." Beautiful example!
Fun fact: the HW 35 and old HW 50 receiver tubes differed only in diameter. Length and stock screw spacing were the same, so they shared stock designs of the same external shape. A dumbed-down version of this stock (beech, no checkering) was an upgrade option in Europe, and standardized by Beeman on his "HW 50S" for a couple years before the R8 replaced it.
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