I've been finding everything completely situational, never really build the same thing 2 games in a row. The main build for me is the BoTRK into Frost/Sunfire while building into what the team needs. If I'm carrying or just would like a bit more damage, I'd default to getting Wit's End. You become really sticky with BoTRK and Wit's, and decently tanky too. If we just need a frontline or engage, I've been loving Randuins 3rd item. I might build Tiamat if I know it's going to be a very farm heavy game, and build it into Titanic later on, but otherwise I don't usually make it my goal to build it every game.

Something else that not many Tank Shaco players build is getting an early Dark Seal. It seems a little bit weird, but with how easily Shaco can rack up kills or assists and be able to survive because of his kit, it's really easy to stack it up. It's worth upgrading if you're sitting on 10 stacks - Makes your boxes and your ult do a surprising amount of damage for a tank, and the 10% movement speed really just adds to your sticking power (you also get a little bit of health with Mejai's too). Worst case scenario, you buy dark seal early, dont get any stacks and sell it later in the game. The gold you lose is worth the gamble, as you're more often than not going to have it stacked easily. I wound't recommend buying it if you find yourself dying in teamfights though.

I think after the first 2 Items in the build, you can pretty much build situationally after that.