The 125B enclosure is here. It comes screws. It's diecast aluminum. It's shrinkwrapped.
The aluminum machining looks way nicer and more finished than what I used to get from the big suppliers before I started sourcing my own.
There are LOTS of different enclosures called the 125B on the internet. Please check my measurements to make sure this is the size you want.
It measures 121 x 66 x 39mm or 4.7" x 2.6" x 1.5"