Similar to the "Darkness Rising" DVD, this one is a re-edit of a story arc into one continuous movie.
This one contains 7 episodes though, with the last four from the end of Season 1, and the first three of Season 2.

23 - One Shall Fall
24 - One Shall Rise, Part 1
25 - One Shall Rise, Part 2
26 - One Shall Rise, Part 3
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1 - Orion Pax - Part 1
2 - Orion Pax - Part 2
3 - Orion Pax - Part 3

Amazon US has it listed for US$12 plus shipping, but it might be released here later, since Darkness Rising was as well.