I bought this reducer/flattener for my rcos 12.5 last year. Never really got around to using it. It was I believe made in Italy, and is mounted in an adaptor that allows it to be used with the astrophysics 70mm fixed camera adapter system.
I know very little about it other than it is a doublet, specifically designed for r/c scopes of around f8 focal ratio.
I paid $500 for it, I will entertain offers around $275
I'll provide images on request, but as they say you've seen one doublet reducer/corrector you've probably seen them all.