Those are 18", I don't know if they are for sale but I saw a post of the owner of the pair when he bought them.
That's a video of the cymbals:
[ame="https://www.youtube.com/watch?v=R6lhgBHlVy0"]Checking my 18†K Zildjian Istanbul Old Stamps: IIIa (1950-1953) 1964 gr & IIIb (1953-1956) 2170 gr - YouTube[/ame]