Here's my idea for you. Stock the actions, magnum, long and short or lets say 3 magnums, 2 long and 2 short. Have the stocks pre bedded to the actions in left hand and then sell them like this or advertise them this way:
2 weeks till it ships, left hand (insert stock, action and barrel description) and then say in (for example) 264 win, 7mm stw, 300 win. You have the barrel blanks and can cerecoat them so instead of one extreme or another you have them prebedded and all you have to do is chamber, cerecoat and headspace (not in that order) and it simplifies how much inventory you have while still having as close to "ready to ship" as you can without all the cost and inventory. What I would say is look at how fast anything left hand is sold in your classifieds! They never take long and us lefties are way more used to paying substantially more than righties. We also go the custom route faster since there are so few " non-custom" options. You would be filling a niche and in this economy anything that gives you an edge is good. Let me.know since I need a 6 mm something.