Electro Valve and Pressure Switch

Hi everybody,

I am building an autonomous ROV that dives using a pump that fills a bladder…
(it is supposed to stay underwater for over a week)…
I have however difficulty in finding two components:

a) An electro-valve powered with 5-12V, able to withstand 10 bar of pressure and suitable for sea water. (This Valve will isolate the Pump from the Sea water when it is not working)

b) I am also building a failsafe system…. If for some reasons the device dives deeper than some expected 65m or in the case the entire electronic fails, a pressure-switch will trigger a simple autonomous circuit that will inflate an airbag.
I therefore need a pressure switch able to close a contact at a pressure of around 6,5 bar.
Again this needs to be suitable for sea water.

(I found both components for clear water, but not for sea water and I am getting desperate…)

Can anybody help?

Thank you very much!