I will try to make him one today, I don't have circular bandages but I have some old toddler clothes from my lil brother that I can somehow cut to fit on him to support his cropI've had crop surgery done on a hen who got blocked up consuming an entire nesting box of hay. There is a video of the surgery. Unfortunately, even after recovery, the crop usually becomes pendulous due to stretching. If you can keep pressure on it in order to help it empty, via a 'birdy bra' it's possible for the crop to shrink down to a more normal size. Unfortunately, crop problems usually return.
I made a crop support using circular bandage. Make sure it's snug but not restrictive, cut out wing holes to hold it in place and it should look like a turtleneck sweater. If it rolls up, cut out leg holes to keep it down.
Once they develop problems emptying the crop, you will likely need to leave the birdy bra on most of the time unless the crop starts emptying normally.