The first draft of the ARINC 661 standard supplement 5 version is available for some time on the ARINC web site free of charge. This document purpose is primarily for remarks from the general public, but you have all the latest standard draft there. Don't hesitate to download it (it's free and legal to do it, what is not free is the final versions of the standard).
The document is here: http://www.aviation-ia.com/aeec/projects/cds/index.html. It's the "Strawman for Draft 1 of Supplement 5 to ARINC Specification 661" link.
If you have questions or remarks about it, feel free to ask about it here or on the j661 project forum.
