Project enclosure with 9V battery

I know this topic has been discussed a bit, but I am still not able to find a good source for this.
I am looking for a project enclosure about 15cm/15cm/4cm with a 9V battery enclosure.
Even slightly smaller width/length is ok. (height I need 3.5-4cm min. to fit a gear motor vertically inside.

Where should I look?
I tried digikey, mouser, otterbox, polycase, aliexpress etc. so far.

Any suggestions are helpful.

RS Components enclosures

No idea what you want to do, or how far you have gone with it but, whatever it is, you might want to make sure the 9v battery delivers the goods before you measure up the box.

Why that useless 9 volt battory? They only power fire alarms, scales and other extremly low current stuff.
Buy some boards, maybe plastic, some glue and make Your own box.