I easily found all those ingredients at my Chinese grocery store. As I learned quickly on the sausage community forums ...
For the Chinese sausage, you can use either plain (lap cheong) or liver sausage (yuen cheong), or both. The meat makes this a strongly flavoured dish, so it is best eaten with steamed rice.
Lap cheong is Chinese wind-dried sausage, while yuen cheong is liver sausage. The best restaurants have their own secret recipes for the sauce that is stirred into the bo jai fan just before it ...