My guess would agree with the seller's description that it is a booth monitor amplifier. It may have been supplied to Motiograph or Simplex. The input is likely a step up transformer feeding the 2A5 pentode output tube grid. The other iron would be a choke and power transformer.

The black and white decals were used from about 1941 until about 1945 when the red, white and blue decals replaced them. Some say simply "Lansing" at the top, while others say "A Lansing Product." Altec made the most of the Lansing name in the early days due to Jim Lansing's prominent standing in the industry. Their tag line on the factory sign, catalog pages and hang tags was "Loudspeakers by Lansing." When Jim left Altec in 1946 the hang tags were changed to read "Loudspeakers by Altec."