Thanks Jeremy. I rang Custom Scientific – as the name suggests they do custom work. They can make a 2″ round mounted V filter for $400 + shipping. Although it is costs more than the 50mm round unmounted, it would save me the expense of a new filter wheel specifically for the larger unmounted filters. TBH, I have a preference for trying to keep the setup as simple as possible and avoid filters wheels if I can. I’ll think about it a little.
However, your comment re Cataclysmic Variables is interesting. I might look into that a little…..