Flockraiser is $17.99 where I get it right now. Several years ago when grain prices were way up, it actually reached $21.99. We get a 10% discount which helps. I do get off brands instead of Purina sometimes but it's only a dollar or two difference.
Stocks of chicken feed have been low around here since summer. So we get some as soon as I have storage space. Of course that's probably because I only know of one city here that doesn't allow hens.
Yes feed is going up . Part of it is crop failures and part is increasing demand. Remember how hard it was to find small livestock last year. Problem is the solution.
There was a time when poultry ate more greens than grain . Then with the ease of grain harvesting all that changed .
if you are thinking for the longer term get some oak trees going for acorn/mast production feed for pigs. some types of acorns are even much better for people food too in a pinch.