sorry to correct, but total number of commercial mauser/sporter in
the time period from 1898-1945 is around 126.500.
out of this number about 40-50% went outside of germany to ( rigby, h&h,
g&h.......
my personal guess is that about 400-600 had been built in 10,75x68, mainly
from german gunsmith. jon might have better figures although i think its really
difficult to have a precise guess.