Q: Where can I find Disc 3 of Mac OS 10.3.5 OEM install discs for a copy of Hardware test?

Take it to an authorized service center.

[X-Lab: The Apple Hardware Test|http://www.thexlab.com/faqs/aht.html]

Apple's AHT support - http://www.info.apple.com/support/aht.html - Apple Hardware Test Images and Information (for pre-Intel Macs, G4 and early ibook & iMac)

Here's the list and downloads for AHT if you have an old G4...

http://www.info.apple.com/support/aht.html

Note:

No AHT available for Sawtooth, try TechToolPro instead.

Some discs require you to use the Option key at bootup to select AHT. Some models have a separate AHT CD.

Is this the 5 CD set? I believe that's the ones I had that had the Discs silk screened wrong , one set had #2 & #3 swapped, & another set had 2 #2s that were different.