Can anyone recommend a heavy, tall, free-standing kickboxing bag like the Tiger Schulmann’s ones?

If anyone has ever trained at a Tiger Schulmann’s, you’ve used their free-standing kickboxing bags. They’re large in diameter, tall, heavy, and the part you punch/kick (the actual bag) extends from the top all the way down to the sand-filled base, no awkward gap or shaft/pipe between the two parts. They’re the nicest bags I’ve ever used because they’re so difficult to move unless you push them, and allow you to really pop your punches and kicks off the surface without that heavy swing, while also allowing you to kick low because the bag extends to the very base. I have never come across bags like that at any athletic or martial arts store, and can’t find any like them online either. They’re usually either much lighter, shorter, have a gap between the bag and the base, or are water filled with a plastic base. Can anyone recommend a similar one if they’ve found it? Cost doesn’t matter to me, so please let me know where and how I can find a bag like it, preferably with a link!