Does anyone know of any custodians that will allow a non resident alien who inherits an IRA to keep the IRA open indefinitely?

I am with Scottrade at the moment and they say that the IRA can, indeed, be inherited by a non resident alien but that NRAs cannot hold an account and they would have to close it and pay out all funds, with a 30% tax withholding. In order to avoid this, I would like to find a custodian that will allow the account to remain open so that my beneficiary can enjoy the benefits of an IRA and make withdrawals at will (as limited by RMD requirements).

Any help would be greatly appreciated.