Good Moderate scope suggestion?

[USMCHunter]

Good Morning!
I have an early Mark V in .270 Wby Magnum. The stock scope is very sticky when changing magnification.
First what would be a medium priced scope option for this? Thinking less than $400
Second would a picatinny rail replacement be a good option? (if it even is an option)

This was my Dad's and I am planning on using it for North Georgia deer hunting.
My Kids are going to use my Ruger 30-06 this year. 
 
Thanks in advance!
Rob

[224KING]

A friend told me about Acadamy having a sale on 3x9x50 Burris scopes at 129.99.Original price was 299.99.I don't know whether it's just a local sale or regional.

[.257]

I have two scope threads, one redfield for $100, and a vortex for $600. If you haven’t noticed them