Hi. Think I have one of those. Problem is we are in between homes and most of my photo odds and ends are packed away. I will take a look tomorrow where if lucky it could be. I know I had a genuine Pentax leather case like you described. Will let you know soon!
Well, found a Pentax case! It has on the bottom a designation of "HG-115" and "Pentax" on top. Let me know if you want it and where to send it if you do. It looks maybe too wide for your 85mm.