I have used 58mm screens from other manufacturers, they fit cleanly, but are a little more difficult to remove depending on the application.

Neither; the diameter of the strainer is 54 mm. It is the sieve that is attached to the brewing head with a screw.

For accessories that will fit/work use this https://www.shadesofcoffee.co.uk/.

Do not go and buy something in amazon as it will not fit as expected. For a review kaffeemacher is the best https://youtu.be/H2fVzUDNJL...

58 to 60