Mwave has Microsoft PS2/USB Optical Mouse for $2.99 + FS for mclub members (free to join)
Technical Information:
Product Description Microsoft Basic Optical Mouse mouse
Device Type Mouse
Connectivity Technology Wired - PS/2, USB
Movement Detection Technology Optical
Buttons Qty 3
Features Scrolling wheel
Cables Included 1 x USB cable - integrated 1 x mouse adapter - external
OS Required Microsoft Windows 2000 Server, Microsoft Windows 2000 Professional, Microsoft Windows 98/ME, Microsoft Windows NT Workstation 4.0 SP6 or later, Microsoft Windows XP Home Edition, Microsoft Windows XP Professional
Package Type OEM
Microsoft Certification Compatible with Windows 7