I don't know the size, but I've got a handful of stainless ones laying around. sometimes you have to carefully grind off a little of the top once they are in place though depending on the valve you use.
Originally Posted by SnowZone
Butcher, do you happen to know what the size of the little set screw that holds the valve (the one that threads into the bottom of the body) on a 2k+? And do you by anychance have a spare kicking 'round?