You can generally pick up a couple 43P's (7043-xxx) on e-bay for a couple hundred dollars each. Most are old CAD workstations and will not come with hard drives. The model 140's (beige cases) are cheaper but limit you to AIX 5.1 or less. I use a pair of 150's (black cases) and they work great for testing nim, tsm, hacmp. As for getting AIX media from an EBay auction it's not likely.