A/C not working 100%

The A/C in the car works but not satisfactorily. I have watched your video and researched a bit, called a VW dealer and have only ended up more confused. I understand their are two types of A/C unit for Golfs, and I do not know which one I have. I want to keep the car but I will not keep it if the A/C cannot be repaired.

I read that I could replace the solenoid pressure valve that is part of the main compressor unit but, I could not find where I could but that part, not available through the dealer. I read that 2008 Golf A/C units give trouble and that it is best to replace the compressor.

I will not be doing the work myself if the system has to be degassed, but I am trying to get a handle on what to do, if I can replace the pressure valve, or if I have to replace the compressor, what brand and model am I best replacing with.

Below is the link to the actual model of the my car. I am located in Australia.
https://www.redbook.com.au/cars/details/2008-volkswagen-golf-edition-v-auto-my09/SPOT-ITM-286508/

VW in Australia said I will have to return the old unit for a new unit, but I would buy a third party unit if that is what I have to do, then I would get an AC technician to install the compressor.

How long should it take to replace the compressor? Ah, the list is endless. Your counsel is appreciated.