This is obviously not fully scientific, but I took the scan of the card in question and overlaid it on a scan of a
1959 Mantle that became a
PSA 5, and matched the sizing of the two separate cards
(based on the picture, logo and text) to ensure it was an apples to apples comparison.
Here's a 55% opacity image of the
'Purple' card on top of my
'White' card, where I lined up the left and bottom borders to gauge the full size of the
'Purple' card:
1959toppsmantle10comp.jpg
The hazy, dark purplish area that
juts out at right is more or less an optical illusion. That is actually part of the
'White' card, which would indicate the
'Purple' card
(bright white border) is decently short side to side.
Again, not scientific, but hopefully a bit enlightening.