Mathematically, I can hit ~16643 block rating, with no block derived from items or legacies (my warden has 170 might passively thanks to might tomes).
This SS shows what I would wear, if I were so inclined to max out my block:
Things missing from this that I've included in the 16643 figure include 2x380 block rating for LI titles, and ~1300 for the shield mastery legacy, that I don't have, but have confirmed the rating on a second age lvl 95 LI (the person had +135x to rating but had put a couple points into the legacy).
The earring was a quest reward, so its unlikely if you don't already have it you could acquire it, but the item isn't exactly make or break as you cans see by the numbers.
There is also a purple agility bracelet that has dropped for me several times from the Westfold WBs with somewhere between 600-800 block (that I've destroyed/sold, so can't link).
We all know parry and evade are cap-able through armour and cloak bonuses, thus not requiring WoS.
The above does also show how sad an itemization state we're in, given that I have to ignore several pieces of theoretically BiS HD BB jewelry (necklace, wrist) and resort to quest rewards and the skirmish camp for specific items, cannot get a single piece of tanking jewelry of value from scaled instances, and appropriately stat-ed medium armour or a cloak flat out does not exist. But it can be done.
Forgot to add, in case you come up ~300 block short of my numbers, I did have "stand your ground" traited when i did the math.