Sorry... maybe you're not understanding my post, or where I'm coming from. My wagon differs from yours, therefore a picture of the 3-2 valves (as there are two on my car as opposed to the one on yours) will not help you out. Yes, I can see your picture. That is the main vacuum 'switch', if you will, for the transmission. It is mounted on the back of your injection pump... as I wrote before, it's easier to test it while it's still on the car. If the rest position on the valve is the same as it is when the valve is mounted in the car, YES, it should hold vacuum... but as I have never tested it outside of it's mounted position, I can't tell you for certain that the valve is set in the proper position to hold vacuum. (and my car is elsewhere right now, so I can't go and look)
Perhaps if you posted some more detailed pics of your engine compartment, someone could be of help to you.( by detailed, I mean a full layout of the engine compartment, and then some detailed pics to go along with it)
Certainly, if it never holds vacuum, position dependent, it is faulty, and must be replaced. Dealer prices will be high, and most likely you are looking at a 2-3 business day turnaround if the part has to come from NJ, or longer if it comes from Torrance, CA. The part itself is in the $200 range. If you need more specifics, I suggest you search 'vacuum' in this forum, and read on... there will be some easy answers to your question in the many posts your search will bring up.
You can also try AutohausAZ.com for parts... they're pretty good. Sorry you don't know how to fix your car, and that it appears we do not understand each other/or that I have been completely unhelpful, and as such, have added to your anxiety... good luck on the sale of your vehicle... the body on it looks great.