Maybe?
Just one of the 6-packs (3 dual packs) at that link.
Maybe and yes, to the latter two questions.
Heck, I’d been thinking of buying some and figuring out how to dose it down for the dogs. As I said earlier, heartworm pills for dogs are a ridiculous racket. One of those $4 tubes has enough Ivermectin for approximately 75 monthly dog prophylactic doses. They want like $75 for 6 months worth in pill form at the vet.
Good idea! You could take that paste and mix it in with ground beef... make little meatballs and freeze them. It’s basically what those dog chews they sell at the vet are.