I do not know a Nepali Punditji but there is one punditji in Livermore Temple he performs for most of Nepali families and is well versed in Nepali tradition. Even though he is not a Nepali his performance is commendable not any less than any Nepali punditji. His last name is Mukherjee. Please visit the temple and enquire the details with the Punditji himself. You can check the directions to the temple at  "livermoretemple(dot)org"