This is a custom comb I first made in February 2016
You can tune the 7 hole any way you like. Here, by lowering the 7 blow, we gain a draw bend. Add 7 blow into the top end blow chord and you get a minor seventh.
You can modify a standard cover plate to fit by trimming away the top end and doing a little folding and smoothing. Sorry, I don't have a photo of the finished product.
I offer Custom made combs here.