Streamer LX is up next as my next option if I can't snag one of these for $2k
The Streamers are a very different animal from the Thumbs - the twin single-coils near the bridge are (likely) what gives them a part of their signature 'snarly' sound. The streamers by comparison tend to sound more 'conventional'.
And of course if the streamer body-shape is to your liking, then give the Spectors a try, since the body shapes are very similar. I think most of the 5-string spectors are 35-inch neck-length, but IIRC there may have been a few runs at 34-inch scale when the production in the Czech Republic was opened (SD-5 spec? with the SSD / stuart spector design logo). IME, if the snarly/grindey tone is what you like in the Thumbs, then the Spectors may sound more similar than a Streamer.