I have a steel cutterhead that accepts replacement knives for a panel raiser cutterhead. It is made by Unique and i naturally reached out to them for replacement cutters. Maybe i am in the wrong here, but they want $70 a piece for the knives, which would be $210 to replace the three knives on the panel raiser. This is 3-4x more expensive than i was expecting. Is this normal? If not, are there other sources for replacement knives where i could send one of my blanks to be copied?