Master Cylinder or Brake Reservoir Screw size ” Please help…

First and foremost. Thanks everyone for such a bad ass forum.

My question is I have a 2013 yamaha grizzly 550 and the screws on the master cyclinder stripped. Part number 98707-04012-00. Anyone know the size of this bolt or what a good replacement hex head would be? Thanks for anyone’s help. Trying to get ready for Mudd Jam and the damn screw stripped on me. Gotta replace it locally and want to make sure I have the right size.