Yes, you can replace the blue mount collar or lever buy purchasing a replacement part. They are available in red, white and black here:
If red, white, black or Quad Lock blue isn't your thing, you can purchase a bike mount collar in other colours as a 3D Printed part. These are printed and shipped directly by Shapeways. As these are 3D Printed parts, the surface finish is not as smooth as an injection moulded part but it functions just as the original.