Here's the Generic North America 4.3 release for Sony. It's untouched, just zipped to pare it down to ~ 450mb chunks.
I've tested this by flashing it to my own device. Even with that, I don't guarantee this to work for you.
If you're locked boot loader, you'll want to look at Nuts thread elsewhere for files to help you stay rooted.
If you're Unlocked boot loader, you can flash this, then flash a kernel with a build-in recovery and root using the update-su file found elsewhere on XDA, then flash the kernel from this FTF again once you're rooted.
C6506_10.4.1.B.0.101_1270-7584 Generic US.zip part 1
C6506_10.4.1.B.0.101_1270-7584 Generic US.zip part 2
I've tested this by flashing it to my own device. Even with that, I don't guarantee this to work for you.
If you're locked boot loader, you'll want to look at Nuts thread elsewhere for files to help you stay rooted.
If you're Unlocked boot loader, you can flash this, then flash a kernel with a build-in recovery and root using the update-su file found elsewhere on XDA, then flash the kernel from this FTF again once you're rooted.
C6506_10.4.1.B.0.101_1270-7584 Generic US.zip part 1
C6506_10.4.1.B.0.101_1270-7584 Generic US.zip part 2