Civil War Era Travel Inkwell

This unwell was a gift from my sister-in-law and it was sold to her as a Civil War Travel Inkwell. It is approximately 2 inches tall. The top opens by a button on a hinge and has an inner lid. The inner lid has an insignia that is a bird ( perhaps an eagle) with two banners at the top and a crown between them. Under this are the letters K.K.PR. When that lid is opened, there is a spring  under the lid and a glass bottle that it fits into. It appears to be brass and another metal. 

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