Do you have any problems with the power supply? Or are you looking to replace the entire system?
If the power supply is still good, you can "realistically" replace the cell and flow switch with an equivalent sized cell (number of blades in the cell), and modify the cell cord to work with the new cell. You can use the flow switch as used in the AutoPilot AG model. The Hayward Goldline flow switch may not work as it uses a phone style connector. You may have to do some modification to your plumbing to get the cell and flow switch to fit in the place of the Autoclear cell components.
That's just one idea...IF YOUR POWER SUPPLY IS STILL WORKING FINE.