Not cheap but excellent quality https://lincolnbinns.com/shop/internet-of-things-iot/raspberry-pi-enclosures.html
I used them for a pair of bespoke Pi 4B 10" rack mounts and was very happy with everything from the project management to delivery time. The face plate cutting and coating was excellent - no rough edges or smudge 'paint' in site.
The HAT may cause an issue for their standard enclosure (it's a total wrap around providing cooling) but drop them an email and see if they can help.
Try https://github.com/gitbls/ndm
It's command line driven but takes very little in the way of memory / processor.