The large white bonnet is extremely wonderful for sun covering and insect protection. I sprayed mine with insect repellent that lasts over 7 washings and wore it into a Malaria prone area in Asia. I got the idea to buy this from Quaker Jane (one of my personal favorite on-line teachers). The white one is available from Originals by Kay under the "fashion accessories" button and then click "millinery" and you'll see that she carries these in different fabrics.
The Grey bonnet is from Rachel's Seamstress Services and it's called the "Elizabeth." This is another of Quaker Jane's fabulous recommendations.
Thank the Lord for Quaker Jane and all the wonderful options to buy things now. When I started covering 21 years ago there was not an "internet" to learn from or to shop from.