I did not think that a card of this level would be a candidate for tampering.
On the list below, the PSA 1 with low eye appeal sold for $150, the PSA 4 MC did not sell at $499, and the PSA 5 MC sold for $750(seems high compared to the PSA 4's listed price).
http://www.ebay.com/sch/i.html?_from...mplete=1&rt=nc
Strictly IMO, based on this PSA 3 MC card having nice eye appeal, I would think that $250 would be a good starting point.