Ok so if i understand that quest u need 10k Moat carp to get the Lu Shang that is around 1.5M for sell at AH on my server.
I've just played and calculate something
10k / 12 ~ 800 (833 to be real)
800 * 3k = 2.4M (3k is the lower price i've seen at AH)
So why make the quest u will earn enough money to buy 1 rod ;).
OK this is rare to find one at AH.