I recently bought this matchbook from the estate of John L. Cronk.
Mahony was a short lived diner company, formed from the remains of O’Mahony.
This matchbook’s interesting in that it advertises not only the Mahony diner company and their Mahony Diner – Motel Center, but also the diner trade journal, Fountain Luncheonette and diner magazine of Rahway, NJ. The inside of the matchbook discusses the virtues of matchbooks as a form of diner advertising.
My other Mahony ephemera.
A Mahony Diner tag, made for a diner that was never built.
Unfortunately, other than its short lifespan and its relation to O’Mahony, I can’t seem to find all that much on the company. I’d love to know more.
Diner Hunter 
John L. Cronk was the sales manager for Jerry O’Mahony and was partners with plant manager Joseph Montano and treasurer Joseph Cavallo in Mahony Diners, which lasted less than two years and built four diners. (Source: American Diner Then and Now by Gutman)
The only Mahony diner known to exist is the Springfield Royal Diner in Springfield, VT, formerly in Kingston, NY. When I first saw this diner in Kingston in 1998, it had three Mahony tags identical to the one in your picture, one in the main diner over the entrance and two on the vestibule walls. It was quite exciting to find a tag for such a rare diner make! But when the diner reopened in Springfield, the vestibule tags were missing.
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