Electrostatic headphone amplifier recommendation

Finding a reasonably priced electrostatic headphone amp is proving harder than I thought.  It seems like everyone likes the blue Hawaii  for my stax 'phones (SR 009) but at $6k!  Yikes!  I'm hearing mixed things about Staxs own amps, that they can be a little noisy.  Looking to spend less than $2500 ( used).