One of things that I acquired when my Dad gave me his old OM-1 camera and gear was a leather lens case. It is the semi-hard case for OM camera with 50mm f/1.8 or f/1.4 lens attached. It’s seen some hard use, but it still looks remarkably good for being more then 30 years old. It does a decent job of providing an extra protective layer to the camera body and lens. However it won’t cover a long lens and I used it primarily on my backup camera with a 50mm f/1.8 attached.
Another downside is when changing rolls of film the entire protective case has to be removed to open the camera back.