'Toy Scout' Encourages Folks to Cash in 'Wicked' Mattel Toys With Porn Link

The Toy Scout, Joel Magee, is advising people against tossing out the "Wicked" toys incorrectly labeled with a porn link ... explaining owners could majorly cash in on the X-rated error.

The toy expert tells TMZ ... he's never seen a mistake like this on a toy before, especially involving a company as famous and as big as Mattel. In fact, he's baffled the proof team didn't catch such a glaring error, calling it a "heavy" misstep.

However, the mistake actually makes the toy even more valuable now ... with Joel encouraging owners to ignore Mattel's instructions on how to dispose of the NSFW packaging.

Per Joel, the resale prices for the misprinted "Wicked" dolls of Ariana Grande and Cynthia Erivo's characters are currently ranging from $140 to $500 ... which is more than quadruple the original price range of $24.99 to $39.99.

Joel credits all the publicity surrounding the dolls as the reason for the skyrocketing price ... but advises resellers to strike now, since the attention will eventually die down.

He adds ... "Now, there's always a chance that they could go up again eventually depending on how many actually appear to be out there. I've seen that happen several times too. But, for the most part, I always say, strike while the iron is hot and go for it."

Joel signs off his advice with one last message ... even if you bought the dolls just to have them, you should still resell them. Take the money and buy yourself the new versions ... since you'll walk away with one hell of a profit.