Any International markets with cheaper commisions than the US ones? China exchange charges 0.1% one way, after brokers added fees, it is 0.15% one way. So buying 1000 shares of $10 will charge $15 (IB will charge $5). 2000 shares of $50 will be $150 (IB will charge $10).
None that I know of. And if they were cheaper you would need a US based broker to settle those trades. And to be sure they would take a vig also.
Open an foreign accounts to trade directly. Do you have ideas about UK, Indian, Vietnam, Korean, Phillipine markets's brokers?