The only restrictions are port size and price, neither of which are broken by this. If the manual doesn’t say that something is restricted or banned, then it isn’t.
What rule number says price constraint?? I found some Parker solenoids that are 12volt, and 1/8" pipe. I assume they are legal, but am having an issue finding any other rule specs.
Technically, the solenoid valves don’t have to be rated for 125 psi if you use a second safety relief valve set lower than the solenoid’s rated pressure. But yes, those are the only requirements this year.