As I hated the stock “fake” CQR, I went through several anchors a few years ago on my B31 Cruiser (2009)…
My first choice was a 20kg Rocna, and it did fit so hopefully would on yours too, but the problem was deploying the Selden bowsprit I have (I was hoping I could extend it through the loop, but no go). If you have a sprit then a Rocna or Delta might not work. If you don’t then both will hopefully fit, but it’s really hard to tell until you get one (and return it, and get another, and retun it…).
I ended up going with a Lewmar Claw (Bruce style). Works well for the bottoms out here in western Canada.
Hope this info is helpful. Good luck.
s/v “Battuta”, 2009 B31