This one, my daughter turned up. It is very practical, as she and I differ in our estimation of the proper amount of milk for a satisfying cuppa. Sadly, the price is breathtaking.
This one is very pretty, though it enshrines a low standard of tea prep (loose tea would look less attractive and also less iconic).
There is also this one, which is 16 oz but is melamine and not microwave-safe, a deal-breaker.
And this one: which seems to be almost the same as this one, except the latter is cheaper and comes with a latex sleeve, albeit one with a coffee bean on it. I could cope with that, and possibly turn the sleeve inside out. It is available at its higher cost at the MFA gift shop in Boston. I wish they made a larger size.