Have you contacted or called Gerry Rodski,
Managing Director at SSB Electronics USA ?
124 Cherrywood Dr. Mountaintop, Pa. 18707 USA
Less than 10 seconds with Google found that web page and information.
The current production model is the TLA-1275-50http://www.ssbusa.com/tlapow.html
As you may know, SSB Electronics is based Iserlohn, Germany - north and east of Cologne.
Here is their German (amateur radio) web page:http://www.ssb-amateur.de/amateur/index_e.html