The mouse looks to be a slightly
modified version of the "PC Mouse". The neat thing is that it is an
optical mouse. :-)
I had an optical mouse way back when with my Mac Plus... I bought it as a
replacement for a broken mouse. I think it was made by A+
At the time, I hated it, you needed a special mouse pad for it to work,
and it wasn't as accurate as the Mac Plus mouse, which made it even
harder to draw.
Just one of those things that I found interesting now that optical mice
are all the rage.