Considering the profit on a Mythril Lance is about 9-10k...
From scratch, an Alchemist with Woodworking and Smithing subs levelled could score quite the profit making these.
I can attest to making about 400k levelling woodworking to 60 in this manner (making the mythril lances for wood skill, and then upgrading them with 100+3 alchemy).
HQ yeild was about 1.5 per 12 synths for the Holy Lance +1.