I Lost a Piece to my Tripod

[WNK]

I have a Gold Coast GT-700 tripod, and over New Years' took it out in the snow to take firework pictures. My hands were freezing and it was dark, so I couldn't really tell what I was doing, and while adjusting the pan-handle the piece that holds it on fell off... I scrambled around in the snow and thought that I grabbed all the pieces, but must have missed the very end screw piece that holds it all on.
I've been searching to try to find the piece, but since I'm not even sure what it looks like, I haven't been very successful. Plus, Gold Coast went out of business awhile back, so I've been having trouble finding anyone that even carries their parts. Is there another piece I could substitute for it? Anyone have an extra pan-handle lying around?

Help?

(also, I'm not sure if this is the best place to post this; let me know if I should move it somewhere else)

 

[WNK]

bump?

Should I place this in another section?

 

[Jeff Canes]

Would any standard screw work? Was it some style of thumbscrew? An old fashion hardware store maybe your best place to look or ebay. Photos would help too