I had my own extension table made by a local plastics company. Had to make a template for what I wanted. It didn't cost very much at all and it fits my machine beautifully. I also had the legs from an older extension table so was able to use those.
If I didn't have this resource I would do something myself as we have had several home made ones posted on the QB. DH of one of the gals in one of my groups made hers and it has a drawer to hold her notions while she sews.
Spending more than I need to is against my economic religion. Well, unless it is a particular fabric, or .....
ali