''which had return'' - ''return'' is used here as in speaking of the ''return'' on money.  It means the gain in value.  The land King Hamlet risked would have been the ''return'' - the gain - for Elder Fortinbrasse if he had won.

''which had return'' - ''return'' is used here as in speaking of the ''return'' on money.  It means the gain in value.  The land King Hamlet risked would have been the ''return'' - the gain - for Elder Fortinbrasse if he had won.

''had return'' - would have been the gain.

''had return'' - would have been the gain.  If something "has ''return''" it's a profitable venture.  From the view of the Elder Fortinbrasse, the land King Hamlet risked ''had return'' for his estate.  It "had profit" if added to his estate.