Prairie View Antiques has posted a vintage Maestro theremin for sale on eBay. Vintage gear collectors may be interested in this item for 2 reasons. First, it's still in the original box! Second, although this instrument doesn't bear the Moog name, it was actually designed by Bob Moog in 1972 for Maestro.
This theremin was known more for its unique "tilted plate" aesthetic than being a great theremin, but you can't deny it'd look nice in your collection.