Really depends on the kind of "streetwear". Bespoke jeans, leather jackets, tees and boots will be easy to come by.

Anything more "exotic" will depend on the specific garment. Lots of adventurous tailors around there, but some items are just fundamentally better suited for mass production.

I don't think you'll need six figure spends unless you want something particularly difficult to make. Everything weird is going to be expensive though, developing a whole new pattern takes a while.

vnapersona bespoke by Maurizio Altieri looks fascinating, I'm not sure how attainable it is though.