Hydraulic Valve Temperature Controllers?

No, but I can make one for you if you have the budget for it. For further details pls use PM channel.

What you are looking for is a temperature activated modulating valve. I have used these in the past and with success.

If that doesn't get it, try Googling "temperature activated modulating valve."

I've designed some simple hydraulic circuits with hydraulic controls. However they were not pretty since the plumbing was not easy. A manifold would be best after a working circuit is tested.

Vickers makes D01 size 4-way pilot operated and cam operated valves that could be used to shift larger hydraulic pilot operated valves to run the actuators.

This kind of control is regularly done in Pneumatic circuits using miniature valves called Air Logic as the control circuit. These controls include everything electrical has except indicator lights that you can see in the dark. I've designed circuits with Air Logic that controlled air pilot operated hydraulc valves to do work in Explosion Hazard environments. However,the air controls can have problems if they must operate in below freezing temperature. Using a Deliquiescent Air Dryer to lower the Compressed Air Dewpoint below the mininmum temperature of he atmosphere thecontrols are working in eliminates this problem.