You may use any fiber just match needle to yarn label and adjust to your tension.

Fiber Spider has not written a pattern for this yet. You may look below video and use transcribe feature to copy, paste and edit to make pattern for yourself.

Video tutorials - Part 1, Part 2, Part 3
https://www.youtube.com/playlist?list=PLocV9YYcJy2TRhhjeq...
Pt. 1 - the brim
Pt. 2 - the body
Pt. 3 - the bind off