Back in the day when I was a kid Roy Gradle made nice left hand conversions using a gear with the bolt. It's mentioned I think in this 1956 issue of Guns Magazine. The prices in this old magazine will make you cry. I takes a while to load.
http://gunsmagazine.com/1956issues/G1256.pdfI believe that Craig Boddington has had a few LH conversions over the years, maybe done just like this.
For me, at my age, while I am sorely tempted and it looks well done, some years back I discovered the Classic LH offerings of Winchester Model 70s and have pretty well filled all my needs.
Oh, I did jump on the Zastava LH sale a few years ago here, and ended up with a 9.3x62. Wish now that I'd gotten a .243 or something in that range too.
Norm