The KO stick your talking about is the Esprit Vantage2, this is the one used by Hirosaka and Spashett. It doesn't have a PCM feature, but it does everything else that you need, aswell as quite a few other useful features. They're also very reliable
You've also got sticks made by Sanwa (Airtronics) and Futaba, the Futaba one will probably support PCM. The majority of people use the KO though as it's just the best!
Your best bet to get one of these would be to contact a hobby shop in the UK as they readily stock stick transmitters.