Hi, few links below for you to look at, the Dave Noble bells are a real quality bell, it's the one in my photo with the brass top on the right of your screen they are 15mm x 15mm....you will need a size 0.
I'm pretty sure the other one's are Lahore bells, tidy enough bells but not the same quality as the Noble, you wont go wrong with any of these.
Dog Stuff - Westweald Falconry - Falconry Equipment - Staying ahead in the field
WWW.WESTWEALDFALCONRY.CO.UK
Westweald Falconry - range of Dog equipment & supplies.