G70 is not high enough to get away without galvanizing, and it is possible to obtain hot-dipped high tensile. It's often branded as "transport" chain in the US, don't know where you are. The galvanizing reduces the tensile strength a little, which is factored into the WLL figures.
As SD implies, you will also require calibrated chain if it's to be used on a windlass gypsy, it doesn't sound like the finishes you mention are likely to be.
High tensile is a good idea as it allows a considerable amount of weight to be saved from the bow of the boat.
There is more info on grades and sizing for anchor chain here, it's an attempt at a fairly complete guide to selecting chain for anchor rode:
Chain (Rocna Knowledge Base)