Is my gear good enough to start tanking HCs at this point?

http://armory.warmane.com/character/...utland/summary

I have 487 defense which should be crit immune for HC bosses. I have 11874 hp unbuffed.

Note: I don't have gem bonuses except for in bracers, belt and shoes. Armory shows the other gear having socket bonuses as well, but they don't.

Get Crystalline Kopesh from the Durn quest in Nagrand. Apart from that, yes, you are ready. Start with MT, Ramps for boots, ring, belt & bracers. Shoulders can be obtained from AC 1st boss, SH last, or SL last.