Actually, discontinued isn't the right word. Vanished is a little more like it.
I seem to recall seeing a USFA listing for a .17 HMR caliber S/A, either on-line or in last year's catalog. I notice that there is no such thing to be found in the current catalog.
Ruger was supposed to come out with a .17 version of their .22 auto. I don't see any mention of it on their web site either.