Hi Simon
I will have to look around for it but I have an Orion Field Flattener that I used for my SkyWatcher 80ED (Black Diamond).
https://www.bintel.com.au/product/or...eld-flattener/
If this is suitable, let me know and we can discuss price. I bought it last year, but we've moved the 80ED over for visual use now.
Cheers