Check out these guys. I have their 80mm triplet, grabbing the 107 triplet from them next year. Field flattener covers full frame even on my 80mm. No import duty to pay on Telescopes but have to pay GST so factor that in.
https://www.teleskop-express.de/shop...elescopes.html
Added a couple of shots from their 80mm and my Sony A99 on an HEQ5 Pro mount.