As I think about it, there may be a little more to it than just finding an empty Singer table. The first photo is a table which held a Singer 603 with a "full size" bed. I put a 15-91 in it but had to add the black "spacer" piece at the right side of the opening, so if you find a table with that spacer in it, you might have to remove it. The second photo is a table with a 15-91 where you can see that the front folding piece has an arm on it to fill in the space to the right of the bed, so this table is somewhat limited on what machines I could put in it, unless I wanted to try some creative wood working.
Have the machine measurements with you if you find an empty table.