Anyone can tell me more about this combined oil temp and pressure gauge? Options

[Marcel Aircooled]

My 1973 914 with 2.0 liter 1974 GA engine came with a non original combined temp and oil pressure gauge. At first glance it looks like a normal VDO gauge, maybe for 911 original but looking closer it seems the letters and numbers are hand painted or some sort of transfer decals. There is no item number and at the back there is also no number or date stamp. Could this be custom made by someone? Here are some pictures







This is the sensor that is installed



The temp meter works but the pressure meter works only from time to time and sometimes drops all the way down or jumps up to the maximum. I took it out and replaced it with an original fuel gauge with just the pressure warning light and a 60mm temp gauge in the console.

Maybe someone can tell me more about this gauge?

[technicalninja]

(IMG:style_emoticons/default/agree.gif)

Quick test/fix.
Take the ground wire off of the brass fitting.
Loosen the rubber coated clamp
Shove bare wires under clamp directly against the metal housing of the sender.
Tighten clamp.

What's up with the weird letters?

I agree, those look wrong to me.