If suppliers are under charging what are they cutting or haven't included in their costs? Are you willing to risk your business sites reputation on it?
So you need to migrate your website. You've been putting it off and say you can't afford it right now. If your site is really old it is also time to review it in terms of your current business goals going forward and update the design.
So when I was building my new site I thought I'd archive older content. According to traffic, that was a bad idea so here you go. For reference the current release of Joomla is 4.x. I always build on the current release and maintain to the latest major release update.
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