I Just looked at Lan-Kwei (
www.lan-kwei.com) and they had a third party one, that i would steer clear of. Gamechoice club seem to have one. (
www.gamechoice.com.hk), however it is a victor one, but these are still good. The model number is RG-VC3. I'd check it out in that FAQ first to make sure it suits your need, but i think that it is a twin operator card.
I have dealt with lan-kwei before and found them to be a pain in the ass. I havent dealt with gamechoice before, but whenever ive emailed them, they've been quick with their responses.
Other than these sites, you could check
www.ncsx.com or Ebay, but beware of shitty cards on ebay.