I think Ballard Design has banquets.

And Google shop it.

Depends on your budget. What is most you want to spend? If tight, might get two simple benches and a small square stool for the corner and see if that could work at least for now.

Some examples. You could put arrangement on riser or leave it empty. Kids always have some electrics that could be put there. A lot less costly than formal set up. A 48” table or a little smaller would work. Same concept if you want a rectangular table and use longer bench on the one side.

That’s very close to our space (60” x 80”) and I think Ballard was the best option when I looked a year or two back. You will have trouble wrapping the corner with only 50”, though—you lose 24“ for the corner itself, which doesn’t leave quite enough for their single seat pieces. Custom would solve that since you could do a shallower bench to pick up more space for the seating, or you could do a banquette bench on only one leg of the L and put chairs opposite. I looked at Barker for RTA custom sizes for built-in options and likely would have used them had we done the banquette. We ended up deciding to do something else entirely with the space, though, so not much help there!