No 150k is way over the top...somewhere around 50k is appropriate- forget the engine and the mecahnicals and the electrics...just check out the shape of the body- rusty and crusty, not rusty but trusty! Body reparations would be very difficult (Desi mechanics ain't too skilled when it comes to hammering out European and American 'real' metal) and body parts are nonexistent currently for early American cars. With later Caprices and others, at least some parts are available (late '70s models onwards).
I WOULD however, pay 150k for maybe a '56 or '57 Chevy Bel Air, or an earlier Impala, providing they're in ORIGINAL condition. I'm looking for a '50s Chevy, Buick or Caddy so if anyone sees one please tell me.
Good luck daredevil!