I havenīt seen the ones that stand on the ground, just the ones for your lap and the ones that stand on a table. Its kind of difficult getting things like the ground standing type, you have to go far afield like Madrid, Malaga or Seville :( . However just the other day I spied a lap one in our local shop, they do a lot of embroidery here.
Like Up North said I think they would be easy made. Let us know how it goes. Elle