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If indeed Apple lacks these discs, this is all the more reason to be wary of purchasing used Macs from people who won't supply you with those discs. Contact the original seller for the discs. If they won't give it to you and you can still contact them, return the machine and ask for your money back. See
my FAQ* for other sources if you can no longer contact them, and remember,
cavaet emptor!
They should never sell you a Mac without those discs, especially if there is any software left installed, as it is only licensed for use with that machine as long as it is installed on that machine.
- * Links to my pages may give me compensation.