Class legal sails are only sold by LaserPerformance or their dealers such as www.sunfishdirect.com or the Tackle Shack in FL, etc. The sails are made by North but you can't go to North and order one. Answer to second question is yes.
if you are not a racer, there are also several options for the non-legal sails at a much cheaper price. APS, Intensity Sails, Neil Pryde all have options, to name just a few.