Ya know what, don't worry about it. If you get a very shaky pup and put it with a family that is very inexperienced and this is their only dog, it is a set up for failure. They want to take the dog everywhere and do everything with it, and it will drive a scaredy dog nutso.
What you are is an experienced dog person who has other dogs. Just relax with the puppy. Do what you would do with a pup if it didn't have questionable limits. Go play on your five acres, and get the pup used to your life.
Going outside YOUR comfort zone and doing stuff, specifically to socialize this puppy, is kind of like making the shy dog the center of attention.
Going out ONCE a week, either to the vet office for a quick weigh and halloo and out, or to the feed store for a quick trip through, look at a few prices and out -- fine. Just loading him in the car, running for a bottle of milk, and leaving him in the car for a 10 minute round trip -- that's an outing for this week.
Just let your stable adult dogs, and your relaxed and experienced self help your puppy gain confidence by not doing too much, too quick.
If you go out every day and meet a new person, place or thing, for a whole year, and then stay home on your five acres for the next 10, what difference would it have made.
Personally, if this pup is still seriously lacking confidence at six months old, I would probably sign up for a beginners rally or agility class, and start usuing some very positive treat-training to help build the confidence. But for these two months, I would just chill with the pup, and maybe take it out once a week for a quick easy something.
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