Low Cost Moveable Goal Options?

Our team budget is a little tight, so we have been looking into making a Vex Round Up field for testing and practicing. We already have a set of field tiles which was purchased by a previous team, and I know there are low cost solutions for the field perimeter, goal posts, and even the ladder.

I was wondering if there are any low cost solutions to the moveable weighted bases, or if anyone knows of a product which acts similarly to the white bases of the moveable goals. Thanks in advance for any help!