The caliber is actually Finnish factory-wildcat 7x53R. A shell is same as 7,62x53R but necked down to 7 mm (.284) bullet. SAKO and LAPUA made this caliber from early 50's to late 70's. Nowadays it is very difficult to find these ammos. That's why I just ordered 7x53R (or x54R so you says) dies fron CH4D.
This rifle has been made to my father in 1963. The maker was gunsmith Aarre Viitanen from Kauhajoki, Finland. When I some years ago got this rifle I decided to customize it a little. So i change the stock and trigger and finally adjust the siderail for scope mounts. That scope in picture is NICKEL but nowadays there is a BURRIS Fullfield on the rifle.