Since I've been asked if this thread is referring to a particular card, I'll spill the beans.
My question was more of a general appraisal of the situation, not perfectly specific. The actual card in question was a 1968 #280 Mickey Mantle graded a PSA 7 ST.
Here is a list of a bunch of straight PSA 7 sales from the past couple of months:
DATE PRICE
6/25/2018 $295.00 7 362355049949 eBay probstein123 Auction 29010693
6/24/2018 $336.99 7 263757761262 eBay emoncards Auction 90223198
6/14/2018 $415.00 7 142821778318 eBay pwcc_auctions Auction 23960047
6/8/2018 $370.00 7 282993806728 eBay tc.8787 Buy It Now 25619735
6/7/2018 $325.00 7 253649975328 eBay azsportsrelics Best Offer 21002103
6/5/2018 $330.00 7 332664729906 eBay chgocubs74 Auction 19978737
6/4/2018 $377.65 7 123152349659 eBay diamondcardboard Buy It Now 29010693
5/27/2018 $315.00 7 312139110876 eBay og60jb32 Auction 07174140
5/21/2018 $432.52 7 153022007174 eBay savannahgator Auction 05042097
5/16/2018 $294.00 7 209 Mile High Card Company Extra Innings May 2018 Auction 29010693
5/15/2018 $330.00 7 132612041941 eBay gregmorriscards Auction 28636439
5/15/2018 $300.00 7 292565095758 eBay texasholdemtom Buy It Now 01517820
5/13/2018 $350.00 7 372287903567 eBay caughtlooking2000 Buy It Now 19978737
5/13/2018 $300.79 7 142775541615 eBay 808resell Best Offer 27636349
5/7/2018 $397.77 7 192499380537 eBay prestonwms34 Buy It Now 27045150
5/6/2018 $350.00 7 332635796118 eBay pean32 Auction 15345337
5/4/2018 $425.00 7 192507525159 eBay scotts_vintage_cards Buy It Now 28183467
4/24/2018 $299.99 7 302714157002 eBay daisywoodyemma Buy It Now 22165975
4/16/2018 $411.99 7 352323923652 eBay pwcc_auctions Auction 28710441
These average out at $350 (with a low of $294 and a high of $432.52) and the lowest straight 7 BIN available on ebay is for $379.99.
After exchanging some messages with the seller (and studying the scans), I feel quite confident that the stains are the sort of thing that could be/should have been easily removed with a pair of your wife's (or your own??) pantyhose.
The card is in an older slab and the centering isn't ideal, but I was able to pick it up for a cool $200, which made it quite worthwhile to me. Unless it turns out I really screwed the pooch, I'll post better/clearer scans when it arrives.
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