Price is for one(1x) transformer, three transformers are available.

I collected Mic/MC step up transformers during vintage time.  RCA (and Altec Peerless 4722 In another eBay listing)  has been known for a good matching with the popular MC cartridges, such as Denon 103/301 and Shelter 501 etc thus in demand since 1990's.

Buying them asap if you know the value of buying from a good seller/collector.