If The Twilight Zone and Doraemon had a baby, it'd be this show.
I was honestly so blown away when I first watched this and how different it is to modern anime you see nowadays. This show isn't about character development nor has a deeper meaning to it, which I think works great in its favor. Moguro Fukuzou is such a great protagonist AND antagonist, but he's usually referred to as an anti-hero.
The plot is very very simple, every episode there's a different customer and it's usually: he/she wants something, or wants to change something about their lives, and Moguro comes in with some magical item or device that always, or usually, comes with a rule you can never break. The customers end up always breaking that rule and the salesman just screws them in the most unfair ways possible. Most of the customers deserve it and some just don't deserve punishment AT ALL. The worst thing is he sets them up to break that rule through plot convenience or just knowing about their urges and tendencies and knowing that they'll break it.
Obviously, this is not for everyone. If you're tired of seeing the same old anime plots and characters rehashed and are looking for something different, this show will definitely please you.
Now, where do you watch the original Japanese dub with english subtitles? It might be simple but, YouTube. There's quite a handful of channels that upload the original series with english subs, so don't worry. Although, if you wanna get into this I'd start with Warau Salesman NEW (the new series from 2017, which ironically has all twelve episodes also on YouTube), because that's how I was first introduced.
It's a shame I rarely see anyone talk about this masterpiece of a show. Because underneath the episodic format of it, is a genuinely great show that I think everyone should have the pleasure of viewing at least once.