Elastic belts are free size and normally don’t tear at all. meaning they can last for life.
I am kind of surprised that they are not commonly recommended in the anti-consumption/ buy it for life communities. Despite the fact that replacing normal belts with them at scale would save the world shitload of resources that are spent on normal belts annually.
Side note: I don’t recommend wearing jeans or suit trousers on daily basis, as there is more durable options that can last for longer time.
Photo is for example, as this is a generic item.
A flea market. Find a local leather worker and they can make one super fast with good quality leather. “Genuine Leather” is one of the lowest quality leathers out there.
You’ll probably need to take care of it if you want it for work. Cleaning and conditioning it.
Personally, I avoid belts that are narrow, like 1" wide, as I think they like to twist more if they have to do a lot of lifting.