How about something like this? It is only 2 3/4" in height. My Wilson Maxx IIs have a clearance of about 3 1/2" from their bottom plates with the wheels on. Still gives some clearance even when sunken into a carpet. Not as pretty as the California Car Cover Co. product and much bigger to store, but might be easier to lift the speaker.
https://www.nationaltoolwarehouse.com/2-Ton-Low-Profile-Hydraulic-Service-Jack-P273041.aspx
https://www.nationaltoolwarehouse.com/2-Ton-Low-Profile-Hydraulic-Service-Jack-P273041.aspx