I’ve only got Browns, and Harum is the only place besides Archon’s site I’ve seen them. There’s a chance someone on AliExpress has them.
That said, Box Creams (or Box Cream stems in Box Silent Pink or Box Silent Brown housings) will give you a linear with similar properties; 5-pin, tapered housing.
If you can’t find ART Box switches anymore, the good news is that their housing design has made it to the V2 of several of their switches.
So you can find this housing type in some of the newer Kailh switches, probably like Kailh Deep Sea or something.
Yes; specifically all of them with the circular stem shroud - but unfortunately none of them with the square one - despite the molds to do it already existing (the ones used on the Archon switches). 
At least in the Western market, most of those are dampened, but at least a couple aren’t - aforementioned Box Cream, as well as the Box Jellyfish.
The Deep Sea does feature the same shape, but despite what some of the sales pages say, it’s not very franken-friendly - the stem is specially shaped to interact with the dampeners in the housing, and other circular shroud stems do fit, but their travel is significantly reduced and I’m not sure they actually function that way or not.
hope they will release a few other type switches with this top housing in the future. 
It seems Hansung TFG ART keyboard is equipped with Artbox switches, but still, they are hard to find…
I might try to find a proxy buyer from Korea though.
This came up in another conversation; these switches have a weird hole on the bottom along with a few other early BOXes.
It’s round in the middle, but at the bottom it has a bent key-hole shape that cuts into the tube, connecting its open space not just to the open air but to the bottom inside of the housing.
One angle of the key-hole.
The other side; looks like drill shavings and such:
Moving the light, though, you might be able to see it’s just grease distorting the other narrow port:
Just beyond that greasy port is where the stem cam sits when the stem is depressed.
Hi !
Harumio here.
We have updated it. It’s in stock now.
Let us know if you have any other products that you want us to sell
Thank you!
You can also see that on Gateron Cap series, they claimed that will make pushing down feel better, while there is an extra amount of grease accumulated around the stem. They have updated the mold and there are some older versions with a clear mark of the hole being filled at the bottom, but after that version, the hole was completely gone.
I’ve ordered one bag of the brown switches, but still, I’m looking for more types of Artbox switches.
