If you want early uncredited Judy Collins, you can often lay your hands on the following at eBay:

Hootenanny at the Limelight/The Wanderin' Five and The Appalachians (Somerset)

I don't know who anyone else on this recording is, but you only have to listen for five seconds to identify the Collins voice.

Railroad Bill/The Homesteaders (Riverside)
with Ronnie Gilbert and Walter Raim

Raim was a close personal friend of Ms. Collins, as she tells us in her autobios.