Early 1957 RSS 22lr Price guide?

Looking for a price range. Buying or selling.

Shooter grade 1957 RSS 22lr 5.5", large Alcoa G XR3, unconverted, flategate SN range SN 55954 but has a roundgate,

400 to 450, assuming the bluing is original.

Flip it over, is the round gate a Premier? Was considered an upgrade of the time.

Not a Premier.

IMO,,, $400 on the low, $500 on the high. If it had the flatgate $600.

All said, it's a nice looking 5 digit, Old Model Action. To me, I would rather own a well used, taken care of gun, old time bluing, some character, nice action, and history say's those 5 digit guns are great accurate shooters, (.222 vs .224 bore)
-vs-
a brand new in the box NM,,, keeping in mind the NIB NM is going to be in the ~$500 range.

My 3 cherished flatgate's with the middle gun being a Premier Gate. All three get shot regularly.