If you want to buy new, go to National MoParts, thats where I got mine from, not cheap though. 1970-6 A Body Tuff Steering Wheel Adapter – National Mo-Parts
I checked Ebay also, and National is probably your best bet price-wise when you take into consideration exchange and shipping
I've got a lead on one from Grampscamp who has come up with lots of good parts for me. If it doesn't pan out I see lots of sources for new ones including Ebay and National Moparts who I deal with often. I've been down to Flatla once but I have never bought from him. He doesn't do email (I've tried) and I don't know if he even sends pics.