I have recently found a bunch of New Old Stock T53 Vane blades marked Huey Engine 1967. The part number is 1-140-211-16 - some with 16N. I have looked through a ton of T53 manuals but cannot find this part. If anyone has any information or a diagram showing this piece I would be very grateful and would be happy to send you a vane blade in return for your help. Attached is a photo of one.