Mod gives you 9999 stack size in survival mod.
I was not able to find any working stack mod so I created one. It was baked adhoc and so it was not tested for every situation. I do not take any responsibility for any damage on your save. Use it on your own risk! Works for companion version of the game.
Edited file: DEFAULTINVENTORYBALANCESURVIVAL.MBIN
Credits:
Neo6891