The Shimano Deore 9-speed trekking crankset was replaced with 10-speed, and the current 9-speed crankset is found in the Alivio series.
The current trekking-triple Alivio crank is 9-speed, with Hollowtech II spindle and outboard BB compatibility. Stock rings are 48/36/26 with chainguard.
I would replace your crankset with this Alivio trekking crank and BB, and you could swap the inner ring with a smaller size if desired. Get a 9-speed 11-32 cassette or similar, and a set of 9-speed bar end shifters, and you will be all set. Very versatile and durable touring setup.