I talked to Conrad tonight and he doesn't have any specs around for the 2000S. When the amp was being made, he didn't do the engineering or documentation of the amp, though he was involved in the genesis and parts selection. They used Schumacher transformers, and he thinks that they asked Schumacher to clone a Dynaco transformer, which they did, but the iron in it wasn't as good as the Dynaco stuff.
Conrad suggested to try Hammond for the power transformer, which I also suggest. You can find out voltage info for the 2000S, add up currents, figure out voltage drops and rectifier conversion ratios and come up with what the transformer should be. If I was going to use it for bass, I would prefer solid state rectification and increased power supply filtering, but thats up to you.
Hope that helps.
Greg