That is a three position Dakota Safety and is very much like the standard Winchester Safety. It requires alteration to three components of the action and one of them is done to heat treated bolt cam and requires a 1/8" diameter carbide endmill.

It can easily cost more to install that safety than the entire action cost in the first place.....

For those that want to convert WWII rifles and actually have something when it's all done.....it's simply takes money....bring it by the shovel full...LOL

I'm fortunate to be able to do these things myself.....I could never afford to hire it done!!