Thanks. I have found a place that can supply near Oxford airport. The downside of a turbine when you have substantial avionics work to do is you can’t just run on battery.
These come with most of the bigger UPSs e.g. 1kW+ APC.
It’s possible I have some at work (Brighton area) but it won’t arrive with you tomorrow either.
Alternatively, rip it out and fit a normal IEC connector. It looks very similar and the leads are common as muck. 28V 40A is only ~5A at 230V AC.
For my new power supply. Any ideas on where it can be sourced at short notice. Amazon has them but won’t arrive tomorrow.