Stems are pretty much universal fit items. You do NOT have to buy a 'Trek ' stem for your Trek bike. First you find out what the steerer diameter is. It's probably 1 1/8". Then you find out what the clamp diameter is. Probably 31.8mm. Now you go to Ebay:
https://www.ebay.com/b/1-1-8-in-Stee...27/bn_77178784
And you scroll through 16,000 listings of stems.

In any event, if you are looking for a tall rise stem, there is the FSA Metropolis:
https://i.ebayimg.com/images/g/7kUAA...cZ/s-l1600.jpg
Very useful for when you don't have a whole lot of steerer tube sticking out but you want a tall stem. I have this stem on my son's bike.