Need help finding new temperature gauge

Woah ! back up a bit a take a wider view. Only 3 parts of the inst panel should get power at switch on... Inst' voltage regulator, park brake indicator lamp, and oil warning lamp.
So if none of those 3 are working you have to guess maybe the 12 volts from ignition switch isn't happening at switch on.
Many times the only thing needed is logic and common sense. A lot of high tech skill and knowledge isn't required.