I can't go as high as $50 because the calipers don't have levers, no FD. Then again, I probably don't charge enough.
I was thinking more like $40, based on what else you had to buy to go with it and make a group; I admit the crank helps, though.
Around here a complete group, ready to bolt on, in 600EX, 105, RSX or RX100, maxes at $80-$100.
(levers, calipers, FD/RD, shifters, crankset)
You shouldn't change the Frisbee.
1985 Raleigh Racing USA - Coleman's Competition
1984/85 Klein Performance
1988 Centurion Dave Scott Ironman Master
1989 Centurion Dave Scott Ironman Expert
1989 Centurion Carbon R