Du coup means something like “therefore, then” but is colloquial.

Du coup, tu as gagné ! → Then, you win!

Pour le coup might mean various things depending on the context like This time, At once.

Pour le coup, tu as raison ! → This time, you are right!

«Pour le coup» usually means “in this instance”, but it can mean “in this case/consequently”.

The internaute site cautions that it is an older usage and generally poorly employed in this sense.

The TLFi entry lacks a specific synonym, but seems to suggest its use as being something like “exactly for this case”.

(The Academy is not very useful.)

J’ajouterai que “Pour le coup” porte une connotation d’unicité(uniqueness) ou d’intensité. Pour reprendre l’exemple d’au dessus, “Pour le coup, tu as raison.” : Cette fois-ci tu as raison. Pas les autres fois.

Alors que du coup, est un simple constat.