Ok ...
What is the full model of the drive ???
Are you saying that you klled the U14 chip on the DRIVE PCB ? Meaning the drive PCB is USB only ?
I was under the impression that you have a external box with a bridge pcb independent from the drive.
If you killed the U14 and the USB bridge on the drive PCB then you can as you mentioned use a compatible SATA pcb and/or convert the USB PCB to SATA by soldering sata tx/rx pairs from the PCB to a SATA port bypassing the bridge USB. But as you stated that you have many SATA PCBs check here :
http://www.hddoracle.com/viewtopic.php?f=7&t=1080Just get a PCB that is compatible with your USB one and swap the ROM chip or re-program ROM on the new SATA PCB.
Now remember the drive will work but the DATA WILL BE ENCRYPTED. So you will have to IMAGE the drive to another one and try to decrypt it with ReallyMine.
Other option will be to buy another PCB from the same model/family of drive (or that have the exact PCB number) and swap U12 to it. This way if the drive doen't have any further problem apart from damaged USB bridge on the old PCB it should work and decrypt data on-the-fly.
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