There are (were) so many non-Campagnolo brands that made either 144 cranksets or 144 rings, it's not even funny. And 144 is still used on track cranks, no?

SR Royal rings can usually be had reasonably, NOS, as can Sugino Mighty or Aero Mighty, or Super Mighty, or Super-de-duper Mighty, or (you get the idea). Gipiemme, Ofmega (=Avocet, too), Edco, SR, Mavic, Sugino, Tevano (TA), Stronglight, Specialized (made by Sugino, mostly), OMAS, Nervar - all marketed 144 road cranksets at one time or another. Check eBay, although the 42s are becoming the most expensive size now, as they are in the highest demand....