If you don't mind me adding to this, Paul, who could provide, in addition to the hinges, the prop/lock mechanism for the vent window (sometimes called the "toll flap".)
I have a different set up - the whole window pivots open a little at the back to allow a through flow of air or the window and be removed completely and stowed next to the seat for a fully open window. heres a pic - the toll hindges are a bit small I think to be of any cooling use.