Yep, I think you're right. I have the original set though:
The front of the box:
(I've seen a different version here:
http://www.vecchigiocattoli.it/atlantic1003.jpg)
The back:
The sprue as listed by PSR:
The extra (?) sprue:
And yes, you're right about the reissue. I have that one too and it looks like it's basically 3x set 1003 in one box (that said, the extra sprue doesn't look to be an extra one after all, maybe PSR just didn't list the quantity of each figure in their review of Atlantic 1003, like they usually do). Just do the math and you'll see.
BTW, another thing I didn't realize until last night is that these figures are HO (1/87) scale, not 1/72. They did look sort of smallish to me.....
And just think, they were first released 34 years ago!!