Where can I buy a used one for around one million?

In Beijing, it's available, but you can't get it for around 100; you need at least 100 to get it.

I've also asked around, and even for a car in not-so-great condition, it's around 170.

You can find this car model in the second-hand car markets in Beijing and Shanghai. The price is around a little over 100, which matches your budget.