You'll have better results searching for a 'Zahle' wax carver than for a 'wax 5'. The one on the right is called a LeCron, too. (Though a Hylin is a similar option)
Check the list of dental tools and wax carvers here
, particularly the more medical-sounding business names; although it's been a while and I don't know how many are still current or how many I've missed that google didn't. If all else fails search for Zahles and LeCrons on ebay - there's usually something on it, and I picked up a couple of good examples for a good price there, meself.