I don't know how much oil it should have in it. I don't know how much oil it still has in it. I don't know if you are running the correct type of oil for the refrigerant you are using.

200ml is just a guess based on a few years experience working on refrigeration systems and the time honoured principal of "its broke now, it can't get any more broke than broke, so try something and see what happens"

If this is a serious project rather than just for fun i recommend you buy a new compressor, preferably one that has been selected to work at the conditions found in the working system.

Jon