low pressure switch

[Dadster1]

I am looking for ideas on a water pressure issue. I have a well with a whole house RO system. I am getting a lot of gas bubbles being drawn up the pump. So much so occasionally (once a week) the well pump pressure drops down to 3-5 psi and with the pump running, fails to get back to the 50 psi I need. When I notice the pressure drop, I shut the well down for 1 hour, turn it back on and I'm usually good for a week. My question is: If this happens when my RO is calling for water, it is not getting nearly enough, and I need a way to shut off the RO. I was hoping there is some type of switch out there that could detect when I lose water pressure and then shut down the 110 supplied to the RO. I have done small electrical jobs but I'm not familiar with anything available for this application. The RO has a low-pressure shutoff, but it hasn't worked in many years and the company was in Tiawan and out of business. Thanks for any help.