Desperately seeking Remote Console Solution

We have couple of  Model 840 Systems with 15 LPARS each which are
running Lan Console . We also have 35 Model 170 On which we are
running Twinax as a console. hence we have approx 15+15+35 = 65
consoles

We are in the Process of Upgrading the 840 to 570 and model 170 to
270's. We are looking for a remote console solution ( preferably IP
based ) as all these systems are more than 100 miles from us

I guess on the Model 570 we have to use HMC for consoles . Is that
Right or Can I have some alternate Console solution like Twinax ?

For the Model 270 we are Looking for Twindata solution or Visara
Solution. In case of Twindata we would need to buy a separate box for
each LPAR..hence for 35 model 270 we would have 35 separate hardware
boxes. The visara console solution is a Linux box with 20 Twinax ports
hence only 2 Linux hardware boxes would be required.

Twindata is approx $900 per lPAR and I Guess Visara would be approx in
range of $20K

Is there a cheaper and better soln than twindata or Visara for so many
LPARS which can be accessed remotely ?