I think it is totally normal. The gurgling is boiling of refrigerant in evaporator as the system is equalising due to your turning the car off. A/C systems don't contain any air, even when there is a small leak as they are a pressurised system. The fact the supply air temp is fine, I believe there is nothing to worry about. Save your money until it's not blowing cold air. Depending on ambient conditions it should be around 4-6C but will vary on ambient conditions being the condensing temperature.
Farwest is right about running your A/C regularly but his explanation is little off with some terminology mixed up. Condenser does the heat rejecting, evaporator is what does the cooling.
https://www.google.com/imgres?imgurl...MygAegUIARC5AQ