On cross-channel ferry in 1962 travelling to Belgium there were disposable coffee percolators in use and they probably still are. You can buy ones that can be re-used and coffebags to go in them.
As an aside I see that there is an American patent for disposable percolators dated 1964. Another example of a patent office not paying attention to prior invention. The Americans allowed a patent for a safety pin in the nineteenth century when the essence of this "invention" was in use in the Bronze Age and ever since, for example.
If you put the grounds into one of those plastic mesh tea infusers that fits onto the inside of a mug, then pour the water over it, I find you get better quality coffee than using filter papers or coffee bags. Or (probably) using a knotted corner of your shemagh, or a Millbank bag
I had some of those coffee bags once, the card hangers kept slipping and breaking, so the open bag of grounds fell into my mug. Wasn't impressed with them at all
Waitrose has coffee pads that are basically oversized teabags. You just put them in a cup and treat as you would a tea bag only down side is that when I last looked it was only a fairly low strength (2 or 3) flavour. Each pad was individually wrapped fo freshness and I have a few in my car for going away with if I forget my cafetiere
Another option that I have tried are the filter cups that sit on top of your mug and you pour through, just like the OP, but are rigid plastic. They weigh nothing but take up far too much space