I make in - frame feeders out of correx offcuts from our local signwriter(freebies) using lath offcuts and all stuck together with gaffer tape.Cheap,hygenic , waterproof and throwawayable if they get too disgusting.The only expense is a roll of gaffer tape for a few pence from LIDL.No nails screws or glue.
I'm going to experiment to see if it's possible to make a substitute Miller type feeder using the same technique.