Waidmannsheil, that's one thing I thought about too, the 8x56 and 8x57JS look pretty darn close, apparently the barrels are the same, and there are heaps of nice 1908 out there (I've seen a couple of beauties reasonably priced).

However, max. CIP pressure for the 8x57 is 3900 bar/56,000 psi, and for the 8x56 MS it's 3200 bar/46,000 psi. Would there be an issue, or were the MS actions strong enough in the earlier models, and only modified in length with the 1924 - which was chambered in higher pressure rounds than the 1903/1905/1908?