I have two burnt 1231c controllers that I could not get a board for as well.
Curtis will not sell them to the public, only to authorized Curtis rebuilders. And the only rebuilder in the world (that I know of) is Flight Systems in the USA.
There website is www.FSIP.biz and they can be reached at +1 (717) 254-3747. They charged by about $500 + shipping to rebuild mine, including all part and labor.
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