Just buy an 80# bag of Sakrete for 4 bucks and fill whatever container ya want. Drive a few big nails into the side and or top. Use a coat hanger to make a loop for a barrel swivel with a 90 degree bend in the crete to hold the hangar in.
Make different sizes/weights cuz ya never know what you will need. Bust 'em off when reeling in the line, it prolly only cost a penny to make it anyway....
My neighbor ran out of the bricks with holes, so this idea came to mind.
__________________
|