It hasn't been printed in decades. Bicycle decks in slipcases aren't terribly common either - aside from special releases, they also haven't been made in decades. They're out there, they were made in largish numbers, but they're hardly what one would call "common" by any stretch of the imagination.
Beyond that, it's hard to say - the US Playing Card Company doesn't keep very good records going that far back and no one clearly knows precisely how many were made. They were a premium product, so for that alone they were probably a bit on the rare side even when they were newly printed.
The New Fan Back design is a very nice one - it was one of the company's more popular designs and has seen many reprints in recent years. I consider it among my favorites.