It will depend on how much of a misprint it is. The face value is 33 cents. A simple mis-print is more of an oddity and might be sold to a collector for a dollar or two.
I'm not sure what the misprint is but there is no collectors market for any attire that has been "misprinted" A fan of the baseball team that the hat was made for would not buy it if it doesn't have the correct logo or "print" Someone might buy it as a novelty but it will not have added value as a collectible.
Price, when issued in 1999, was 33 cents See (scroll to bottom) : http://alphabetilately.com/G.html KDC
From pe.usps.com they have pictures of the stamps. An H rate stamp with a HAT is worth 33 cents, and an H rateMAKE-UP stamp with a picture of a Rooster is worth 1 cent. Please look for yourself.
190k
The USA H first class flag top hat stamp, issued in 2012, is typically valued at its face value of 45 cents. However, its worth can increase among collectors depending on its condition, rarity, and demand. In uncirculated condition, it may fetch slightly more than its face value in the marketplace. For precise valuation, it's best to consult a stamp catalog or a professional appraiser.
350 coins
its only worth about fifty cents
A signed Clayton Kershaw hat should be worth about $400-$500 maybe more or less
$1.oo
Like $38
hat
The Dale Earnhardt 1998 Daytona 6468 of 15000 hat is worth 5.99 US dollars.