Perhaps you know some folks out on the farm with hens and roosters, who can donate some feathers your way throughout the year. But, living in the city, I only know a few folks that as urban chicken ‘farmers’ have occasional wind falls of feathers. The sometime errant feather can be found in the coop or out in the yard.
The catastrophic raccoon can cause havoc for the ‘girls’ and yes may find a pile of feathers, if that. And, then there is the sometimes molting that can take place in the Fall or Spring an result in quite a few feathers.
Put you word in with the owners that you are interested in those feathers, especially if they own any especially caped hens (or depending upon city regs…a rooster).
Most of the feathers are not for wrapping a hackle collar, but rather cutting out sections of barbs for wings on wet flies (paired or singular).
Tend to the possibilities for all manner of feathers as fashion trends/fads periodically diminish the more high end feathers. Yes, you can go to the shops and craft stores, but you will learn to keep an eye out on walks for the wayward feather, laying there all alone and of perfect quality for a few wings. Friends, once prepped will save feathers for you. All good and enjoyable in the creation of your worthy offerings.