[AT] Late 1950s Case Tractors

[LeRoy Price III]

For awhile the old tractor bug has been buzzing and was thinking about a 
Case tractor of
the late 1950s.  I've seen a 300 round nose but never the one with 2 
headlights in the front.  I've also seen Case 400s but again not with the 2 
headlights.  I also know there was a 500, 600 and so on.  I'm also not sure 
when the 430, 530 and etc came out either.

Could someone give me a briefing on these tractors?
Do these come up for sale?  I don't seem to see any.
Many made?

LeRoy