Hey So Cal Desert.
You don't need the whole kit. Just a couple of washers will do.
You'll need the rubber float washers and the fiber cap washers.
I recently bought 100 rubber float washers from Hydroscape. I had to order them. When the washers came in they charged me 2.10 each. I was livid. I'd never paid more than 79 cents before. So I went online and found them fore .46 each. I bought another 120.
Washers
The 3/4 inch fiber washers are all pretty standard. One size fits all.
The 1 inch fiber washers come in two different sizes. I believe yours is the smaller of the two. It will be the standard 1" fiber washer they sell.
The 3/4 inch rubber float washers are all interchangeable.
The 1" rubber float washer are in two different sizes. I'm pretty sure you have the newer style. With a smaller hole in the middle.
You wont be able to buy the older one with the large hole in the middle. If you have that you'll have to replace the whole float.
Your valves don't look that old so I'm thinking the parts they in the new kits will fit.
I could go on and on but your best bet is to take the parts with you to an Irrigation Supply House. Try Ewing, Hydroscape, John Deere Irrigation.
A coulpe of tips. I see in your picture, the valve adapter had that little nodule sticking out on the bottom of it right above the cap. It might be in the way so you can't get the cap off or back on. You might need to loosen the adapter a bit.
Also scrape any calcium build up off the brass pin the float slides up and down on. I use a small screw driver. Also clean any debris from inside the plastic float.
Good luck!
Now that I said all that. The kit they sell at the Home Depot should work. That is if they still have them.