I'm creating a very simple 2-3 page site for a small business, and would like to be able to include a small table that includes dates when the office, or a particular person, may be closed/out of town.
I want the client to be able to update this information on their own. None of them are particularly competent with computers, so the ideal is to allow them to only have to edit a single file, and then just have the contents of this file inserted into the main page at some point I specify.
Something akin to an Apache Server Side Include would be more or less perfect, but I want a solution that doesn't rely on some sort of server method (which may or may not be available with different hosting providers). I've considered, and eliminated for various reasons things such as templating systems, client side scripts, and iframes. What I'm looking for, is some kind of pure HTML server side include mechanism I may have overlooked somehow. Does such a thing exist?

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