I'm REALLY sorry that this has happened to you and Ricky. It has happened to me and my dogs too, as you know. I agree with you about the spikey suits and collars. I think they prevent the owner from picking their dog up and getting them out of harm's way.
After our work big dog encounter, where Dave was knocked down and trampled. We DID get pepper spray and carried it. For a while. Then we would forget. The other problem is that they get out of date, and there are several dangers. If it's a REALLY dangerous dog and your aim is not good enough, you can just enrage them and they can come at you instead of the dog. The bigger danger is that with the slightest breeze, it will get in your and Ricky's face too. So every time you have to weigh the risks and danger there too.
With the short-range stunner, you have to realize that it is LIKELY that they will already be in contact with Ricky if they are that close. Meaning HE will get shocked too.
There are no easy answers. Just other things to think about.
There is another tactic that will stop most dogs in their tracks. That is to throw a handful of kibble on the ground between them and you and Ricky. If there is an owner involved, this gives them a chance to get there. If not, it gives you a chance to make a retreat. In general, I find it easier and faster to get a handful of kibble into my hand and thrown than it is to get a spray can out, engage the trigger mechanism, make sure it's pointed in the right direction and spray. With kibble, close is good enough. And the further it is broadcast, the more time the dog is going to take to find all the pieces.
The other tactic is just a big long walking stick. And if the dog continues to come, bring it down as hard as you possibly can across the dog's sensitive nose. It is already in your hand.
So these have become our standard walking tools. They are easy to remember and easy to use. We were taught to use the walking sticks when hiking Cape Breton in Canada, after there had been some Coyotes attacks on humans. No one was to walk in the woods without a walking stick and all dogs had to be on 6-foot leashes. The point was that hitting a coyote (or dog) this way usually does not cause lasting harm, but it DOES teach them not to go after dogs or humans. And they were working REALLY hard to retrain the coyotes in their parks to stay away from humans.
I figure that if the "nice way" of scattering kibble and having a friendly but firm talk with the owner doesn't work (you've already set them up to not be defensive toward you, because you just gave their dog treats, so they MIGHT be more likely to listen to YOUR needs and those of YOUR dog
) The stick will protect you and Ricky, is not likely to hurt you and Ricky the way pepper spray can, and you can use it without getting as close as the stunner seems to need you to be. (though I have no personal knowledge of those)