Searchers of Mystara

From the initial blurb:

Searchers of Mystara is an adaptation of Nicholas Dessaux's "Searchers of the Unknown," designed for starting an old school game in the northern reaches of Mystara. It should be particularly good at creating a "funnel" experience and helping players come up with characters that will feel at home in the campaign world. Although you could use it to run an entire campaign for years on end, you'll probably want to switch to a more fleshed out game after a few sessions.