Just in case you weren't aware, The Oregon Trail is on Steam as a remake now, but I haven't read much about it. I like the colorful style they chose for it though. There's also the still unreleased Journey Express which looks very similar. Anyway, here's some other stuff:
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Organ Trail is the closest to Oregon Trail I think you can get on Steam. Players control a group in the zombie apocalypse instead of journeying to the western frontier.
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Death Road to Canada captures the same sort of travel with small events interspersed that Oregon Trail had, but plays quite a bit differently..
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Super Amazing Wagon Adventure is an Oregon Trail-themed shooter.
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The Flame in the Flood is about traveling by raft but more about survival in the modern gaming sense than Oregon Trail was.
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FTL is super well known, but pretty comparable. You could also try Trigon Space Story.
All three of those games are fantastic! You might want to check these out too:
And of course the big ones like ToME, Caves of Qud, and C:DDA are all amazing. But you can get ToME and C:DDA from their original sites for free.
Hope you enjoy Northern Journey!