Is it permissible to trade shares of foreign companies that produce permissible goods (halal) and do not deal with Islamic banks, through an Islamic broker, while disposing of the usurious portion of the profit?

It is not permissible to contribute to companies that deposit their money in usurious banks, because that involves dealing with and being content with usury. Therefore, the fact that the company's original dealings are in permissible things, or that it intends to dispose of the usurious interest, is not a justification for contributing to it.