The first two just came out a while ago (October) so it will be a while before they are on Blu ray. You might be able to find a cam if you wanted to enough but...
The first two were just a recap of the series. Probably mostly the same animation with different editing.
Just a heads up, you might want to prepare to update this soon. It suffers from no-progress bug that is currently under rapid debugging. Scheduled to be fixed on May 1st at 22:00 JST.
It's out, update please. 聖騎士リアナ to v3.5