Super high quality reproduction M1907/M1917 Feldmütze or Krätchen. This was the standard headgear for all German forces before, during, and after the First World War. Available in a few different styles, these are sure to be great with your Imperial impression.
(If these look like they have a bit too much flare, don't worry as the one you'll receive will be more square shaped, even though multiple shapes/styles can be seen in original photos.)
These come with Prussian Kokarden but you can change them out as needed.
NOTE: These are made-to-order items, and are usually available in 4-6 weeks tops. Each hat is custom made, assuring top notch quality. Buy with confidence!