Can't be many left.
off the top of my head.
Donald - alive
Ernest - dead
George K - dead
Lee - dead
Robert R - dead
Telly - dead
Charles - dead
John C - dead
Richard J - dead (during wiki though he died recently but no awhile ago).
Wiki-ing
Jim B - alive
Ralph M - dead
Trini L- alive
Robert W - dead
Clint W - STILL ALIVE!
Tom B - dead
Ben C - dead
Stuart C - alive
Colin M - alive
George R - alive
Sorry didn't have time to cut and paste the whole names but most of you will have seen the film a dozen times or so will know who I mean. All the big guns and mains are dead apart from Donald Sutherland. Some of the backing crew are still around notably Jim Brown and Clint Walker.