There was one that sold not long ago online, but unfortunately I do not recall the exact price it was listed at...but want to say it was north of $2000...
Typically, left handed rifles were priced more than right handed rifles from the manufacturer, as they had to retool and produced fewer (less than 1% of rifles produced were/are LH).
While in some configurations they may take longer to sell...typically left handers are on the look out for such rifles as yours and they do sell fairly quickly. The popular Model 70, in a DG caliber such as the very popular 375 H&H, being one of those, as they are few and far between. (If I didn't already have a custom 375 caliber rifle, I would be interested.)
While 10% of the population is left handed, almost 30% are left eye dominant (such as myself) and shoot left handed rifles.