You could make your own Huel bar/balls, that way you only need drinkning water, probably less water! 
Here is a great receipe:
A home made alternative to Huel bars? Poor mans Huel bar
You don’t have to follow that receipe, if you want to make it cheaper just use dates and a little bit of oats to make it bind together and them form bars or ballz! Add maybe Raisins if you want more texture/fun, they are cheap!
Good luck!!