Mac Pro Installation/Restore DVDs

You could call Apple Support to see if they still have copies you can purchase.

Contacting Apple Customer and Support Service

1. Apple Store Customer Service at 1-800-676-2775 or visit online Help for more information.
2. Primary support help at Contact Support.
3. To contact product and tech support: Contacting Apple for support and service including international calling numbers.

Otherwise, look to Amazon or eBay or Google search.

Perhaps you noted the recent content prior to edit. If not, then

you have some footwork (online, etc) to track down a source.

User Groups - Apple

Join the club. Find a user group near you. ... Find an Apple user group

near you with this handy tool from Apple User Group Advisory Board ...

https://www.apple.com/usergroups/

Good luck & happy computing! 🙂

Have you tried your local Apple retailer or, if there is one, a local Apple Club? Here's is a contact who may be able to help you: ***. He runs a large Mac Club in the Cupertino area. You may tell him I referred you.
[Email Edited by Host]

They removed it again. So, do this instead. Locate the closest User Group to you: Find a Group | Apple User Group Resources. See if they can help you out.