In reply to TRip:
I think it would be worth listing the age of these cams and when they were last reslung. BTW you can post them to BD for reslinging and rewiring, this is completely free apart from getting the cams to BD (which isn't that pricey I just paid 12:50 for 3 cams)
I sold mine on using the formula of:
price = (current cheapest new price * age) / 10, as much beyond 10 years old I think cams start to go wrong (broken springs, fraying stem wires, worn lobes around the axles and on the outside etc) and aren't really worth much / as safe as they should be.