Samuel Wyly and the estate of his brother Charles should pay $329 million for using offshore accounts to hide stock holdings and engage in illegal trading, regulators argued in seeking to increase the penalty ordered by a judge, Bloomberg News reported yesterday. Wyly and the estate should pay that sum plus an undetermined amount of interest, a U.S. Securities and Exchange Commission lawyer told U.S. District Judge Shira Scheindlin in Manhattan today. In September, the judge found that the brothers must pay $187.7 million plus interest, which could push the amount to more than $300 million. The bigger penalty, if accepted, could more than double what the agency is owed, according to court filings.