Several people liked this post which I took as interest in the mentioned archive of source and headers for TI's public releases of their msp430 gcc toolchain. I've now made this available on github at: https://github.com/pabigot/msp430-elf
There's nothing you get there that isn't from TI, but it can be useful to determine what changed in each release, so you know what to look for in the upstream gcc repository.
Updates to this repository will be best-effort on my part: no promises.