Wicht
Hero
Presumably you're after top quality and all the rights for such a princely sum. That'd be $400 for 10,000 words - no residuals.
Actually $400 for 2-3 days worth of work is not a bad rate. But it may also be more than the publisher is going to actually be able to pay and still break even on a PDF which may only sell 30-50 copies a month.
Did Van Gogh cut off his ear and drink loads of absinthe, (probably not in that order), for the sake of thirty pieces of silver. I think not; he did it for his art