509146 Custom meta description for Joomla1.0/Sobi2/sh404sef website

I have an old site built with Joomla 1.0.15, Sobi2 RC 2.9.1.0 and sh404sef 1.3.8 - build_337 and I'm looking to improve the sef friendliness. The sef URLs and page titles are just fine (it writes the category names), but the meta description is the same for all the category pages (over 30,000 pages, the Joomla global meta description). I need a solution to create meta descriptions on all pages that look like: "Looking for a {business type} in {city}? Browse this page or search on [login to view URL]" -where {business type} and {city} are category titles that can be taken from the Sobi2 fields. The text and {fields} can be different, but that's the idea. If you create a plugin like the Virtuemart and the other plugins that come with the sh404sef component I would need a Joomla 1.5 version too.