Oil pressure interlock

["K M" <symbiotic@hotmail.com>]

I want to put an oil pressure switch on my car that will shut the engine off 
if the pressure drops below. . . whatever is a maintaining pressure. Does 
anyone know of a company that sell such a thing?  I imagine that it would be 
a simple switch that interferes with the positive post of the coil and has 
some kind of a starting bypass.Of course, one wouldn't want the switch 
cycling. Thanks, Kim
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