Well it depends on where you live and how available they are. The white spotted is harder to get than the banded so I would suggest it to be priced higher than the banded. I don't know what the demand is for sharks where you live but here in Nova Scotia Canada i'm the only one I know of that has sharks of any kind in captivity. I ordered my banded bamboo eggs from a specialty fish store and got them for $80 each.
If your shark is allready hatched then I would fairly have to suggest you ask around $200, and if it's still in the egg you should ask $120. You have to be carefull though since if your call for sharks isn't high then you may get stuck with it for a while if you are asking too much.