Don't believe there is any place out there that caters to lefty's only.
Since only 10% of the population is left handed, and only 10% of the population hunts or shoots, that makes for a market of just 1% of the population, and many manufacturers do not seem to think that the cost of retooling their manufacturing lines is worth the trouble. This is why there are so few manufacturers making left handed firearms.
They do not seem to take into account that approximately 25% of the population is left eye dominant when they are making left handed firearms.
Most reputable gunsmiths will order in left handed actions that are available, but most will not carry them all regularly in stock. If they do, they will be in the more common action lengths.
I have seen builds on Defiance and Borden actions in left hand. Very nice actions. Definitely not budget actions.
It can be more cost effective sometimes to find a left handed rifle to use as a donor than ordering a left handed action; but this takes time and research, as the SA's in left hand are a lot less common than the LA's. Price will vary accordingly.
Rugers can be very scarce used (I missed the one that has been for sale here twice in the past year as it sold in moments, both times), but it is nice to see that they are making the new Hunter rifle in 6.5 CM and the Scout rifle in 223 and 308 Win.
Remingtons come along more often, but you got to be vigilant or in the right place at the right time, as they too do not last long.
CZ is making a lh SA rifle (527), but only in 223, if you are a mauser fan.
Sorry, haven't kept up on the Savages.
Sako does make 3 different model 85's in LH; the Hunter, the Bavarian and the Finnlight II. They do offer them in XS and S, SA configurations. These are not a cheap option though, as they are higher quality firearms.