MacBook Pro Power Supply Options
Your solution is probably going to be two things:


Institute a regular inspection program - don't wait until things break. When you notice users bending the cables two months after you issue them is when you need to train the users to not crimp/bend the cables (to budget for users that are hard on the equipment so you have spares on hand when they break them).
There are no aftermarket MagSafe adapters made to better specifications or materials than Apple's  - only cheaper knock off and imitation or just less solid but well designed and built. You would need to armor or stiffen the cables before they fail with added material if you don't want to train users.


If your users are breaking the accessories, you'll want to train them and explain how tightly wrapping or always bending the cord in the same exact spot will break down the materials faster than if they spread the bends across a larger area or just keep the bend radius larger as opposed to a sharp right angle bend.


https://www.wired.com/2013/12/tnhyui-macbook-powercord-wrapping/


Note the loop and the straight cable on both the MagSafe end and the power brick end. Also, note that Apple has ditched this design in favor of easily replaceable USB C cords so people that are hard on cables won't need power adapters going forward - just cable replacements.