It looks like a modified factory stock... Or someone made their own custom stock for it.
You will love the .25-06 caliber. Especially if you open it up to .25-06 AI and get .257 Wby velocoties out of it.
I found this old bdl varmint special in 25-06 for sale. and I have never seen a stock quite like that on those rifles.
The stock looks like it was made by Reinhart Fajen. they were very popular for people that liked fine looking stocks.
They were very nice stocks when you could get them. They are still in business but I haven't bought one in years.
J E CUSTOM