It might take a little digging to find the blank but it's doable.
It is highly unlikely that he had blanks custom made to his specifications. That would have entailed a very hefty up front cost for mandrel sets and minimum production time, etc. That's in the neigborhood of $10,000 plus. My guess is that it's a spey blank, or a noodle blank.
The logical reason he became short with you when asked about the blank is because it is not anything special. Otherwise he would have just told you that they were his brand.
