You could get a rear wheel with an internal 3 speed trans and then put your 6 speed cluster on that.
That will give you 18 gears! You'll find your climbing gear in there somewhere.
It might sound strange but I've seen it done. Do you know an aging bike mechanic?
If you know a good one? Ask him... I bet he smiles when you do.
He should be able to build you a rear wheel using your rim with new spokes and trans hub.
A great site for ideas.
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