No, I hadn't thought of that. Do you recommend any shop in particular? Is there a better way to find/contact them other than start calling HK distributors?

Regarding wider, I don't have much choice. Is it better to go taller instead?

Say to go from 150/60 R17 to 150/70 vs. 160/60. +15mm seems like a big jump in diameter for the 150/70 vs. +8mm for the 160/60