Dan, if it is a stud leaking it is an easy fix as the head can be left in place. It is basically just resealing the stud and retorquing.
In the above the water runs over the top of the head~~not uncommon.
If the head is cracked it can sometimes be fixed via welding and a resurfacing of the head. Or you may just find one from a member with an extra one and there is always a brand new MMI head
.
Dave Neptune