There are probably more cars out thee with the plugs in the manifolds than have the smog equipment. It got tossed by original owners pretty quickly. Some guys purchasing an original car would get lucky and the original owner may have just boxed it up.
Some of that original smog stuff sells for ridiculous money now, since it is scarce.
But, yes if you want the motor to appear original you would need to locate the smog. You can always remove the guts of the pump, and just have it for looks though