Isn’t it 50hz 380v in the UK? There should be plenty of psu’s that plug in over there to 48v DC or whatever you choose for under $100usd. Just a quick look at aliexpress there is this US $408.64 10? Off | 12V/24V/36V/48V/50V Switching Power Supply Input 110V 220V 380V AC to DC LED Smps 4000W Adjustable Power Supply
https://s.click.aliexpress.com/e/swzP0I4g. That’s $400 however I’m sure you can find them for less. eBay has a 380v AC to 24v dc for $20 so whatever is needed there should be something compatible so he can use what he needs.