How do you value chaos orbs?

[:1]If I want to ask someone to make me something that requires Chaos Orbs....err...I can't exactly buy the mats...what do I do?|||A common method I've seen is that the 'customer' provides the other mats and the crafter provides the orbs, usually at around 500g to 1000g each.|||check on wowhead: http://www.wowhead.com/item=52078#reagent-for