It is no longer possible to sell the chestpiece back and get your tokens back to allow you to imediately buy the Brew of the Month membership.
It is possible however that if you bought the goggles you won't need to buy the hat for Disturbing the Peace.
Also, fret no more. Disturbing the Peace isn't part of the Brewmaster Meta anyway. Did Blizztards Change that?
So when you have 200 tokens, buy the Brew of the Month membership first and then work on your gear.