JB
I got mine from Don Pilling and it is very nice work. I went with single bar also. He makes them to suit your kit but as yours is an older Dax he may not have design details etc. but he knows most cobras so he may have details. I am sure he would make one up for you based on your own design though, just need good mounting points to secure to chassis etc. Are you looking at a bar with the third leg? That's real fun to get the hole in your body right!!
Leeroy