Well, to get the Ash Hat you must have chosen Pikachu when you started your journey and must complete this quest. About the Fox Mask, this item is usually given/won while PvP tournament, or if you're lucky enough to buy one from someone else, then this item can be tradeable.
For the rest (Talisman, Red Ribbon Bells, Blonde Wig and Plumber Set), those items are for now not available for players, but who knows one day, they will be probably available through quest or event !