I've seen VINs for XX 500s as low as 110xxx.
Be leary of any 500 that was in central FL in the late '80s. In '88, I came across a 500 in a junk yard the had all the 500 parts and VIN numbers removed. The number on the trunk drip rail was a cut out area about 1'x2', the car it went may show signs of it being spliced back in. I wish I could recall the color of the 500 shell, that would be a big help to spotting a possible rebody out there.