Sorry to hear about your predicament Yosako. I was stuck in a stock (MAAL) because Penson declared it non-DTC eligible despite it being a very profitable and well-run company.
Like you, I am a foreigner, so I was not allowed open an account with most brokerages. (Fidelity, Ameritrade)
You also have to avoid any other brokerages affiliated with Penson (as there are quite a few)
Google discount brokerages in the US and write to all of them for advice. Other than that, can you put in a good-to cancel order with Zecco pre-specifying a certain amount sold each time such that you don't need to constantly call for phone trades? I really don't know.
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