牛渕簡易郵便局

A cat's paw. You can purchase hand-crafted accessories and the money goes to sheltering cats.

小笠郵便局

A steaming mug of tea.

小笠丹野簡易郵便局

川上郵便局

Area famous for tomatoes.
*Banking window closed for lunch (12pm-1pm)

菊川駅前郵便局

Major region for raising of Japanese rice fish.

静岡県菊川郵便局

Most likely, it says 茶どころ or "the place for tea" with an image of a freshly picked tea leaf.

横地郵便局

Mt. Fuji, visible over the fields of Yokoji.