Buy a piece of 1/2 plywood
Cut it lengthwise in two even 2 ft wide pieces lengthwise then cut those long pieces into four 24 inch squares
You can cut these pieces in Home Depot on their panel saw
Then buy a tube of floor adhesive or “liquid nails” and glue those two sets of four pieces each together and stack a couple 45 s on each to “ clamp them while they dry
Probably about $35.00 total and you’ll have two each two inch thick blocks that are each two foot square