Question for you boys and girls;

Let's say you bought an old Gardin road bike frame for $150 with (15 year old) dura ace brakes, levers, deraillures, etc. and a (6 year old) ultegra crankset / bottom bracket and modolo stem and bars... Let's say that you found a hairline crack in the head tube and a bunch of rust and decided to return the bike but think that it would be worthwhile holding onto the parts - what do you think a fair price would be for the components?