Thanks for the new pictures.
My first impression was the rifle came out of the Wundhammer shop. I've only seen that buttplate on a Wundhammer, the schnabel and layout is a lot like his work.
But it all ends there, the checkering and checkering layout is not his work and the stock is way to thick. You can see this where the Lyman 48 had to be inletted into the stock.
The inletting is not his and there is way to much wood removed for whatever reason. Did the stock break because if the missing wood, Or was the wood removed in an attempt to repair the stock.
Ross King worked in his shop for sometime before he went on his own but the work does not look like his. I'll check my files because I remember that someone else worked for him for a while.
Regardless of who did the work it's well worth some effort to restore it. Good luck....MP