Anybody have access to large scale printers that could put these on signs? This is excellent counter protest fodder.
It's not hard to break a picture up into "panels" and print one per printer-sized sheet. Then just trim off the white margins and tape them together into one giant poster. This is how billboards used to be produced (might still be, for all I know).
Some image programs will automatically print sections of an image on multiple pages if you tell it to scale the image larger than a single page size, instead of letting it auto-fit the image to one sheet of paper.