If he wants a "scout" rifle that comes as close as possible to Coopers concept the Ruger GSR would be my top pick. The Styer and Savage would get a look. I had one of the original Savage Scouts briefly. The newer version is a much better rifle.
Personally I don't want a true scout. I don't want anything to do with a forward mounted scope. In fact I firmly believe that even Cooper would revise his specs with today's optics and rifles. And the Ruger GSR and Savage will allow conventional scope mounting. I can't say about Styer.
His recommendation of a forward mounted scope was primarily due to his use of military rifles which could be loaded via stripper clips which couldn't be used with a scope over the action. With DBM rifles holding 5-10 rounds available, plus much better optics that allow quick target acquisition when mounted conventionally they are no longer needed. In fact are in the way.
I do like short, lightweight, handy bolt action carbines with low powered scopes mounted conventionally for a lot of uses. And there are lots of options. I have one of the Ruger Predators in 308 that takes the 3,5, and 10 round AICS magazines that fills the scout role for me. Cost me $395 shipped + $5 transfer fee.
The GSR is a very good rifle, probably better. But not $400-$500 better to me . I'd be paying for features I don't want. But I'd not advise anyone to not buy one, they are good rifles.
Steyr does allow for conventional mounting but the rings must be in specific positions.