extracting string

Hi!

I have an issue extracting parts of a string in a more complicated situation where I cannot split by delimiter.

The initial table as well as the final desired output are shown below. Please note that before the ":" delimiter between the name of the organisation and the corresponding country there may be several commas. Also, the name of the country may include a comma e.g. "Korea, Republic of". This is really giving me headaches... Thanks in advance for any tips.

initial