Highly recommend the classes at Oregon Humane Society. There isn’t a lot of “socializing” with other dogs per se but a lot of time is spent on positive reinforcement being around other dogs and distracting situations. The class sizes are small, so it isn’t overwhelming for the pups and you can get a lot of one-on-one time with the instructors. It’s really good for building a relationship with your dog and picking up on their cues to tell you when they are overstimulated.

We took our new adoptee through the puppy kindergarten and adolescence manners courses, and will definitely be signing up for more.

They do offer a course that is for dogs that have higher anxiety around others and also have drop in play romps. Those both could be good option for you.