Good luck in your search Dan - I obtained a non-powered GM&O A unit several years ago and began a search for the matching powered A. Asked here, 'watched' Atlas F3s on eBay, and tried to buy a cab from Atlas. All to no avail. Along the way I obtained a Santa Fe F3 A powered unit that was beautiful. Didn't match the GM&O however so I kept looking.
Finally, after about two years, Bill at Atlas came up with a GM&O cab and sent it to me. I pulled the Warbonnett shell and painted the silver chassis, trucks, and pilot. At last I had a proper AA pair.
Yes, the dummy should have lights but I don't remember about the magnetic coupler but probably does.
Hope you can find yours much quicker!