Surely with your Chinese connections you can source a suitably sized chuck at a very modest price 
The problem isn't sourcing the chuck - you're right, I could probably find a corner shop in Zhengzhou which sold them (I'm not joking either - you get the strangest shops out there... one of them sold compressors and electrical switchgear - and nothing else!
Literally 2 minutes walk from my wife's apartment is a small estate full of such shops, and it's all cheap as chips (compared to UK prices). However, I didn't see any machine tool type shops, I suspect they're further out of town - or quite possibly in another town entirely.
The problem, as usual, is how to get a rather big lump of heavy metal back to the UK? Put it in a suitcase and it's bound to set off all kinds of alarms - and will probably use my entire luggage weight allowance, and I doubt I could sneak it through customs either! Which brings us to postage, which is where anything from China loses a big chunk of it's value-for-money, sadly.
PS: There's always the "leave your clothes behind..." approach
i.e. take a small suitcase with enough clothes to wear out there, then abandon them in favour of a chuck... unfortunately I can't easily buy clothes out there, I'm way bigger than most Chinese people, they just don't stock clothes in my size!
