As always with Leeson... talk to Clive.
I have an XXL and I think there are a few XL's out there. Last I heard he wasn't keen on a 660 with a seat, but I suspect he's changed his mind now he's done some 609's. I reckon the chances of you getting a pic of an XL with a seat are the same as you picking up some hens teeth on ebay...
Jon