Shenzen isn't fun.
Head to Foshan and dig some IBM SSKs or whatever valuables you can find.
Foshan is an e-waste dumping ground.
Agree. Most IBM SSK that found in Taobao is from GuangDong Foshan. Some of the seller even can get up rare things such as Kinesis Advantage.
For 1st hand stuffs, try to get a Keycool then. It is currently quite a heat in China and go as low as 330RMB(TKL) and 400ish for full. Quite a dirt cheap price.
If you are adventurous and just want another random board(not cherry switch), go for Rapoo v7(TKL) which cost below 260RMB.
Poker X should be cheaper in China if you can found them.
Lastly, KBT Race is also available in China but it cost more than the price stated in the sticky.