I have a sugestion. It may not be possible, but it needs to be analyzed first before saying it is or not.
What about using a microcontroller ? There are some really cheap and fast ones in the market. Microchip just released their new PIC32. It has a MIPS core and runs at 75Mhz.
I believe it could be done with something smaller than this one. Microcontrollers seems a good alternative to replace the CIAS