.22 shorts are still readily available... I have two Winchester 1906's. But, both of mine will take shorts, longs (long since defunct) and long rifle ammo (as marked on the feed tube). Both rifles are amazingly accurate!
I not seen a 1906 that only takes shorts... In either case, the 1906 is a fun toy! The safety isn't all that good on these and you can "pull though" it if you squeeze enough. Also, you can hold down the trigger and pump the action for western style rapid fire!
John