I thought I had counted your stitches accurately.
Could a Glengarry not be made from a round bonnet, blocked into a Glengarry shape? Knit it and felt it just like a normal round bonnet, but use a taco shell holder (or something similar) to block the wet felt. If it didn't work, you still wind up with a round bonnet (after rewetting).
The Folk Hats book has an unfelted Glengarry that's made similar to yours, except the crown is knit in two halves, each growing out of the side band, and then the center sts are worked together with Kitchener stitch (grafting).
Bookmarks