The Seventh Edition licensing procedures are, I suppose, still in effect, 
though I doubt that tapes are available from AT&T.  At any rate, whatever 
restrictions the license imposes still exist.  These restrictions were and 
are reasonable for places that just want to run the system, but don't allow 
many of the things that Minix was written for, like study of the source in 
classes, or by individuals not in a university or company.

I've always thought that Minix was a fine idea, and competently done.

As for the size of v7, wc -l /usr/sys/*/*.[chs] is 19271.

-- Dennis Ritchie, 1989