"J"-hook style crest

[Gaivs Antonivs Satvrninvs]

Hello,all,
I wonder if anyone knows the dimensions of the "J" type crest box. I'm ready to try my hand at making one and need to know height(from the top of the helmet) and the width. I assume it to be the same thickness as most other crests. I'm not concerned with the horsehair itself but the holder. My plan is to make it from wood with a brass covering.
Sorry if it's come up before. If so, please direct me there.
Thanks.