Ehoff is probably right, depending on what butt plate you get. The deeply curved ones will require removing quite a bit of wood.
What I think you need to do is to order a catalog from Track of the Wolf.
Their catalog has full size photos of every gun part they sell. Notice, I said "Full Size".
That allows you to measure the picture and measure your rifles butt so you can buy a plate that is the right width and length, with the curve you think you want.
Be warned that these butt plates are rough castings. They requre a lot of sanding and sometimes a little filing.
You should also know that although you can reduce the width of a plate you like but it looks too wide, the amount you can reduce it is limited.
The limit is due to the fact that most of these castings are somewhat hollowed out leaving about 3/16 if an inch of "land" on each side so if you want to reduce the width more than about 3/8 of an inch, you will be cutting into this hollowed area.
If that happens, you will have your hands full trying to get the wood to match whats left of the surface.
Let us know what you decide to do.
zonie