Don't know if you're considering solenoid valves for the flow of lquid through the rig as well but I just found ones one EBay that are working extremely well for my rig.
The guy has a ton of different kinds.
I went with 1" port, viton seal (heat resistant up to 270 degrees) with 110V coils. They have 1/2 orifices in them and when open, let everything flow through perfectly.
I'm not trying to sell anything and I don't know the guy at all... I just relaly like the valves and they're a really decent price for solenoids.
If you're interested, you have to touch base with the guy and let him know you want the 110V coil and viton seal... they don't cost extra.
Electric Solenoid Valve 1" 24-VDC, Water, Diesel (B21N) - eBay (item 300284294312 end time Jan-31-09 20:37:11 PST)