This is one of the most popular games on the Famicom; similarly, it is often counterfeited. Ebay sales place this game selling for around $500 - $550. One of the tabs is unfortunately broken here. The label has some "damage" which is common on these carts due to the glue that Sunsoft used on their labels. 
 
This Gimmick! is 100% authentic - we can't take a clear picture to show you, but the PCB is correct and only contains one jumper, something that only the official Gimmick! pcb used. 
 
Here's a chance to make this gem of a game part of your collection for a reduced price.