1. There have been recasts of Shinki parts available on Taobao, and a while back we had a rash of "factory rejects" available. The former should be easy to tell apart, and the latter, as far as we can tell, are real Shinkis stolen off the factory line by a worker; current theory is that that's partially responsible for the current lack of Shinki, as Konami needs to go find a new factory. However, I haven't heard of any bootleg Shinki, if that's what you mean by fake.
2. Yes. All Shinki that I know of come with four gun-holding hands with the trigger finger pointing almost straight out; one pair jointed, one pair fixed.
3. No clue.