If you can't get the landing card, you can only give it to won at the black market remittance office here, and then tell him China's card number, and then let him make money. Generally, Koreans or China food stores have handling fees, and they directly depress the exchange rate to make profits.

If you have a landing permit, you can consult the Bank of China in the middle of the road (I don't remember if it is in the middle of the road). You can look it up online or ask someone else.