Which heads are you talking about for $650? The summit heads are a stock valve job refresh with a core charge. I don't see a core charge on the Aero heads but I maybe blinded by the quality and price.
These with 2.02 are $599.
ARO-CY-SB340 1968-1987 340-360 A-Engine 1.88X1.60 SS Valves, (2.02 Int. Valve add $100.00) 67-70cc Open Chamber Design, .509” Lift Springs, 160cc In. Port Volume........ 499.00
