Check, compare and upgrade a Joomla component

I have a joomla site which uses a modified copy of JUser 1.0.12 and I need to upgrade to the latest version. What I need is the current component uninstalled, the new component installed and then everything put back to a full working state. I need this work done asap with no loss of data. Budget is $30 and I am ready to hire someone right away if you are ready to begin straight away.