Could have either axle.
Look here:
http://www.camaros.org./l30m20.shtml#axle
Being a four speed, probably the 275 horse engine. Original to car?
If original drivetrain, I think Buddy is right on. Could bring a bit more.
Need tag and other numbers to know.
Now that you posted it, you have to worry about someone finding it and buying it out from under you.