hi wbd,
my first reaction when reading your thread was-- is there any thing other than woodward???
I do however remember working on an aged system by Foxboro a long time ago (before them new fangled computa gyzmos)> It was pnuematic and ran a small lp steam pump. I have not kept any technical sheets for it so I can't help there directly but I suggest trying the likes of Foxboro, honeywell and rosemount they may help.
Another place which may sound off beat but I do think will help is the hobby enginner club sites. You know the guys with steam tractors huffing & puffing around on sundays. A lot of companies advertise their wares thru these clubs
any way they are my suggestions for today. If I have anymore I will post them.
Regards
Don