Stockton Rim in California will make them for you-there was another company on the east coast-but I think they went under....haven't seen them advertise in the last 2 years. Used to be a guy in Ky that made race car rims but he died of cancer IIRC in 2003. You might Try Rim and Wheel in Ohio to see if they have a custom wheelwright-it's a long shot....and there is always the possibility of making your own if you have a metal lathe and some 5/8 steel plate but to make 6 adapters will take a few hours....took me 8 hours to make 4 adapters about 15 years ago and I knew what I was doing at the time.....best I can come up with off the top of my head-but will give it some thought.....send us some pix of your rig If you get a chance......geofkaye