Price of tube chassis?

I agree with PFogel. If you have the time & skill, get a kit & do it yourself. Keep in mind any potential rule changes during the build & build it for a class. CM will probably be more expensive than MS unless you can swing a deal somewhere. Doin' it that way & some whellin-'n-dealin' for parts, you could probably do a rolling chassis to your liking for 8-12k.