Antiques Week in New Hamshire is August 4 to 12, this year. It is the place to be.
It is New England's premiere summer show, so there is lots of Pennsylvania ...iana there, along with the New England stuff.
The Annual New Hampshire Antiques Show is the best show of its kind in New England" (Maine Antiques Digest)
You can find information about the shows Here, and Here, and Here, and Here, and Here, and Here, etc.