Inserting File Attributes Into XSLT Output

Using XSLT 1.0, is it possible to insert linked file attributes during
a transformation?

For example:

My XML:

<dao linktype="simple" href="ms0778.01.07.pdf" actuate="onrequest" show="new"/>

My XSLT:

<xsl:template match="dao">
<xsl:variable name="dao_title" select="preceding-sibling::unittitle/."/>
<xsl:choose>
<xsl:when test="self::dao[@role='bio']">
<img class="bio" src="{@href}" title="{@title}" width="180px" height="225px"/>
</xsl:when>
<!-- Default handling, loads object in a new window -->
<xsl:otherwise>
<a href="{@href}" target="_blank" title="{$dao_title}">[Digital
Archival Object]</a>
</xsl:otherwise>
</xsl:choose>
</xsl:template>

XSLT Output:

<a href="ms0778.01.07.pdf" target="_blank" title="Personal.
1916-1965.">[Digital Archival Object]</a>

Desired XSLT Output:

<a href="ms0778.01.07.pdf" target="_blank" title="Personal.
1916-1965.">[Digital Archival Object, 2.5 MB]</a>

Many thanks,
Nathan