I went to a local house they were building, look for a neighborhood that has a lot of construction. When they build the garages they have to trim the laminate beams they put above the garage door opening. Mine is 5.5 inches thick and 14 inches wide. I gouged out the place that the wheels on the floor jack sit on the wood, so the jack sits on its belly on top of the laminate beam. Its very steady and I can jack the car all the way up to the height I want on the jack stands.
I usally ask if I can have the beam scraps, just to make it "legal". the framers usally don't care, they know its trash.