From the info you have supplied, you're spot on with regards to these being the speakers Gilmour uses, except for one (tiny) detail: his are 15 Ohms.
Unfortunately there is one vital bit of info missing in your list: the Type. There are several Types of Crescendo: 'A', 'B/L', 'L/T' and then some.
Gilmour uses Type 'A'. On the black&white or red&white sticker it will say what Type they are.
http://www.gilmourish.com/?page_id=70
But 4 Fane Crescendos NOS: are you kidding me?!? This is
everyone's wet dream! This happens once in a lifetime.
If they are 'A's, don't worry about the 8 Ohms or 15 Ohms. Get them NOW!!!