well, AFAIK the Mirage IIICJ was made in france, all of 'em.
you're maybe mistaking with IAI Dagger, no?
btw, not new this story...its BS IMO, specially for the pollitical point of view.
http://www.acig.org/artman/publish/article_274.shtml
Israel was in an weapon embargo by france, the main weapon supplier, and they're were trying to get be with arabs for the oil, and even today france hasn't a great relationship with Israel.
btw, some Dagger parts came in 1972, but Israel had also an partnership with Dassault to built an better Mirage using IAI Technology....some units were built unfinished in Israel, so they had to wait till the war end to put the J-79 on it.
the stolen blueprints story maybe or maybe not fake, that's because IAI Had an partnership with Dassault, so they probably had acess to it already.
that's what i hear/read here also.