Filtering a datasource by range in the Symphony CMS

Question

I'm currently working on a website and have run into a major problem. In a recent question I asked how to filter my XML with XSLT based on the content of a series of XML nodes. The end result was this:

<xsl:if test="listings/entry[available-weeks/item[number(.) &gt;= {$url-min} and number(.) &lt;= {$url-max}]]">
    //my listings show here...
</xsl:if>

Now, while this works just fine, it isn't going to work for me because I'm also using pagination so what happens is the pages paginate as normal and then decide whether or not to be displayed. Since this sort of filter can only be done in an XSLT template I need the equivalent for the data source.

Does anyone know how this might be achieved?