I used a wide-tooth comb as a warping raddle with a rubber band across the top of the teeth to hold the threads in their slots. After I got the hang of it, it worked surprisingly well. Somewhere I posted some pictures.
Warping and then weaving the gamp was so cool. I never thought I could do it and I did it. I was walking on a cloud for days!
I'll see if I can find where I put the picture of my makeshift warping raddle and send you the link.