Having just done a long metrical text in Early Modern Irish, it would  
be nice to move to other end of the spectrum for a change: a prose  
text in Old Irish.  The successful candidate should

1) not have been translated within roughly a century, or ever;

2) contain a predominance of OI verb forms that did not get  
regularized during the course of scribal transmission; and

3) not exceed a few pages in length.

Does such a creature exist?