new evolution items

None in the current batch of gen 3, but later on we'll get Clamperl, which evolves into Huntail when using the Dragon sea Tooth, and Gorebyss when using the Dragon Sea Scale.

Neither item currently exist in Pokemon Go.

No Gen 3 was a bust all it's doing is increasing my pokemon storage and the amount i transfer...

Technically Feebas to Milotic uses an item. However it wasn't introduced until a later generation. At launch you had to max its Beauty stat before it would evolve. This matter for contests and most players were happy to see it go.

No one can say how it will be implemented in Go, but a new item does seem likely (along with 400 candies)