Hello there my fellow AmiBayer's

I am looking for ZIP ram...

20pin 1MWordx4bit 71c4400az at 70ns or faster (512kb)

I would like as much Zip ram as possible. so if someone could find me a link or has some for sale (there used on octagon SCSI cards to name but one)
or even if some one knows of a compatible product that i can get hold of, please message me

[edit: updated]