Here is a direct
LINK to the page that the EPROM is on. If you have an EPROM prgrammer that can program 27C400 EPROMS, then these are what you need.
Nathan
P.S. Postage is the same, even if you buy a few of them. Australia Post charges the same rate from 0-250g for international air mail. Same for Australian buyers, postage is the same whether you buy one or several.