I just did a quick search and couldn't find any but it's no problem to pick up one when I go to the local electronics store. I'm there pretty much every day...
I had a set once which would only work properly when fed by the N-1000 adapter. If I hooked it up to a Stax amp then the bias came and went. Very strange hence me being curious about any issues.
That does bring up a question in my mind, why doesn't Craig transform one of these amps into a Stax amp by simply using different output transformers? Many people like to use the SRD units with SET amps so why not cut out the two high ratio transformers and just use one low ratio unit.
Very strange indeed. One plausible solution would have been oxidation on the tube pins which was scraped off once you reinserted the tubes. A stretch though...