Just HaPPy to Be Here

A blurry shot of a sign over a news stall at Reading Terminal, which reads HaPPy. The two capital Ps are clearly from another set of letters.

Seen in the Reading Terminal Station.

This news seller clearly got these letters from other sources for bargain basement prices. It drives me crazy every time I see this sign because I know, I know, I’ve seen these letters in a logotype/logotypes before. Anyone have any guesses where these letters originated from? My brain will thank you.