Coolant Temperature Switch - Early e30 45degC switch

[TB123]

Does anyone have a source or or alternative for the 45C switch (2 prong exposed spade terminal switch)? This is no longer available from BMW.
Part numbers: 12631279716, 12631279722

[TB123]

I also should have asked about the function of this switch. Obviously, it's just a simple open/close temperature switch, but what specifically does it do? It looks like the circuit goes to the DME.

[varg]

Can't help you with the source but here it is in a wiring diagram to give you some idea about its function. I don't know precisely how the idle control unit responds to it, but if I had to guess I'd say it switches a stage of cold/fast idle off when it closes. I say a stage because there are other temperature inputs (0°C switch, coolant temp sender) which may be used for an even higher idle after true cold starts.