pressure guage

Hello there My daughter just purchased a house and she had a plumber to replace 2 radiators After bleeding system and radiator fitted, plumber couldn’t find pressure gauge on the system Here are some photos . Ideal es38 combi Any suggestions

Hi I have a pressure gauge on the outside pipe just before it enters our house. It has started leak. Is it just a case of turning the water off then swapping it for a new one. Do I even need a pressure gauge or could I just close it off? Thanks in advance Kev