Well, the T50-2 is "officially" for the black 85/1.9 Canon LTM. But it will work perfectly on this lens. It may not reverse nicely on the lens for storage.
The "official" hood is chrome, with Series VII threads on the rear, coupled with a Series VII to 48mm screw-in adapter. Ideally, there's a 48mm reverse threaded cap to go over the adapter when the hood is reversed on the lens for storage. Early versions engraved Serenar, later ones engraved Canon Lens.
Alternately, this hood may be found with a Series VII to 50mm push-on adapter, particularly the early Serenar version. Works just as well, although more prone to scratch the lens barrel. There's even a 52mm slip-on lens cap that fits over the adapter when it's all reversed for storage.