did sharon stone ever play a bit part in the movie 'husbands" with
peter falk,ben gazarra, and john cassavettes in 1970?

Dear Difficult, 

The IMDB (Internet Movie Database) that lists the official cast [and
sometimes also uncredited] for the film doesn't list Stone as a
participant in the film.

Full Cast and Crew for Husbands 
<http://www.imdb.com/title/tt0065867/fullcredits> 

It lists Stone's first role, as a "Pretty Girl on train", in "Stardust
Memories" (1980):
Sharon Stone (I)
<http://www.imdb.com/name/nm0000232/> 

Note: in 1970, Stone was 12 years old and living in a small farm town,
Meadville, Pennsylvania.

I hope this answers your question. Please contact me if you need any
clarification on this answer before you rate it.

thanks so much for the quick response.  had i looked further i would
have realized she would have only been 12 years of age.