I built LibreOffice 3.6.4 using a lightly modified version of the Arch mainline PKGBUILD. It took about 7.5 hours (build directory on USB3 disk, with -j2 ), including packaging, and includes all architecture specific packages. From my limited testing, it works really well. You can add localisation from the mainline libreoffice-xx-NN-3.6.4-1-any.pkg.tar.xz packages (en_GB is fine here).
Currently, the binary packages are hosted on my ISP web hosting at
http://seyrsnys.myzen.co.uk/arm-lo-3.6.4, you should get a directory listing from which you can download what you need. wget -r may also work. In future, I may add a binary PKGBUILD to the AUR, though I'm not promising to maintain it.
Grateful thanks to AndyRTR for an excellent mainline PKGBUILD, the only changes were to remove junit and fixup the md5sum of a patch that had changed in git since the mainline release.
A great test of the Chromebook build, which ran at dual core 100% CPU almost the entire time.
The packages are:
$this->bbcode_second_pass_code('', 'total 73M
1.5M libreoffice-base-3.6.4-1-armv7h.pkg.tar.xz
4.0M libreoffice-calc-3.6.4-1-armv7h.pkg.tar.xz
47M libreoffice-common-3.6.4-1-armv7h.pkg.tar.xz
4.0K libreoffice-draw-3.6.4-1-armv7h.pkg.tar.xz
6.3M libreoffice-en-US-3.6.4-1-armv7h.pkg.tar.xz
152K libreoffice-extension-nlpsolver-3.6.4-1-armv7h.pkg.tar.xz
356K libreoffice-extension-pdfimport-3.6.4-1-armv7h.pkg.tar.xz
208K libreoffice-extension-presentation-minimizer-3.6.4-1-armv7h.pkg.tar.xz
324K libreoffice-extension-presenter-screen-3.6.4-1-armv7h.pkg.tar.xz
2.1M libreoffice-extension-report-builder-3.6.4-1-armv7h.pkg.tar.xz
88K libreoffice-extension-scripting-python-3.6.4-1-armv7h.pkg.tar.xz
680K libreoffice-extension-wiki-publisher-3.6.4-1-armv7h.pkg.tar.xz
316K libreoffice-gnome-3.6.4-1-armv7h.pkg.tar.xz
100K libreoffice-impress-3.6.4-1-armv7h.pkg.tar.xz
48K libreoffice-kde4-3.6.4-1-armv7h.pkg.tar.xz
248K libreoffice-math-3.6.4-1-armv7h.pkg.tar.xz
184K libreoffice-postgresql-connector-3.6.4-1-armv7h.pkg.tar.xz
20K libreoffice-scripting-beanshell-3.6.4-1-armv7h.pkg.tar.xz
592K libreoffice-scripting-javascript-3.6.4-1-armv7h.pkg.tar.xz
1.9M libreoffice-sdk-3.6.4-1-armv7h.pkg.tar.xz
4.5M libreoffice-sdk-doc-3.6.4-1-armv7h.pkg.tar.xz
2.4M libreoffice-writer-3.6.4-1-armv7h.pkg.tar.xz
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