Yeh. The hockey puck thing with hoses is the amplifier, or more correctly, relay I would think "as to function." The round dealie on the fender is a tank, nothing but an empty cavity. Part of it's job is to keep the heater, AC other vacuum stuff working when you press on the gas and the manifold vacuum drops.
To the OP. Do you need this for an emissions inspection or for "resto correct" look? Otherwise I'd figure a way around it.