I need to get some spigot rings to fit my Volk Racing TE37's.

I know that the Subaru hub is 56.1 mm but the simple task of measuring the the wheel is proving a nightmare as I can't get the vernier caliper into the space. An old fashioned ruler makes it look about 60mm but wanted to check if anyone could confirm this or even suggest a supplier?

Cheers.

 

various spigots available on ebay last time i was looking for some