Now just for hahaha .....is your stock worth anything.
Before you go trying to make it look all pretty it may be better to sell it and buy a new stock from CMP,dupage,cmp,DGR,wenig or such.
I recently finished a late 50s HRA I found at yard sale to go on my CMP HRA service grade that came with new wood.
I cleaned with dish soapy water, gave it a wipe with lacquer thinner and then 3 applications of 100% tung oil. I have just found 100% tung oil the easiest to use for me. For the new production wood I have used min wax tung oil finish. I have also used linspeed , Tru Oil, Danishoil and boiled linseed. All work well and if you follow directions all work well. I prefer any "treatment" that looks like it's in the wood vs the on top of the wood finishes like poly and shellac.
The cmp article is a good and will get you going.
For most of my other usgi stocks I use the basic oil and cheese cloth clean up and end it.
HRA stock refresh - Album on Imgur