I had this made for my Orc rack, it’s 12"w x 10" tall x 10" deep, I think it’s some kind of x-pac fabric, with internal plastic panels. Has a sleeve that fits over the rack tombstone, two pouch pockets on the back, a clear map sleeve on the top, a pouch on the front, and sleeve pockets on the sides. There are two removable straps that can be used to secure it to your handlebars (which I used), or you could set it up for decaleur life.
I think i’m going to sell this bag, if anyone wants it for the same price. it’s a little big for my drop bar situation.
Shipping stuff is kind of a process these days, but i can still get it done.