All of the bootloaders for d800 and a couple for d801, packaged as flashable zips.
Ensure you download the correct version for your phone! Improperly flashing your bootloader (or flashing the wrong one) will result in a bricked device.DownloadMore on XDA
These are flashable packages that install the bootloader partitions. There is a zip for each stock d800 ROM and a couple for d801.
Included partitions are aboot, dbi, laf, persist, rpm, sbl1, and tz.
These packages flash all of your bootloader partitions. Modem/Radio should be flashed as a separage package.
10d & 20c were extracted directly from tot file.
20y & 30f required flashing my phone to 20c, then did FOTA to 20y and extracted the partitions. Then FOTA to 30f and again extracted the partitions.
You muse ensure your ROM, boot, recovery, and modem/radio partitions are all compatible with the bootloader you flash.
You can't just use the newest version to "fix" things.
There are really only two ways to know for sure. Either flash a bootloader package or manually extract your bootloader partitions and examine the files.