My bet is that the existing stock could be Devcon Bedded and repaired to the pint it iwll never crack again. I have fixed a lot of cracked Mauser stiocks and it is actually pretty eay to do. Done right you won't be able to tell it was ever cracked.
Otherwise, Bill in New Norway would be my choice to. There is a LOT of hand work and finishing required to complete a stock that is just duplicated, but it will have the exact pattern of the existing stock.
Boyds Mauser stocks tend to be very full and quite heavy. Also, Boyds sells an unfinished walnut stock that can be trimmed down as much as you like, only problem is it needs to be checkered when done.
Here are some before and after piks of a Mauser stock I slimmed down, it took about a pound and a half off the guns weight.
Before
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Same Stock After Trimming and reshaping.
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