lol, yep, same channel I saw them on as well.
Please keep in mind that sushi is one of the many, MANY subjects I am ignorant on (other than it is usually raw and I like it) so my suggestion might not mean much... however given that I am fairly ignorant I will give it anyway... lol
I would say if you don't have much money but want a decent knife for stuff like what he does on the "How To Make Sushi" channel, buy a Fujiwara FKM or Tojiro DP knife. I would probably lean towards the thinner Fujiwara FKMs, as I think that would help with the sushi. Remember, the fit and finish on the Tojiro DPs and Fujiwara FKMs will not be at the same level as what the Mayabi knives probably are, and most certainly not to the same level of some of the more expensive Japanese knives. However, keep in mind that with Tojiro DP and Fujiwara you are getting very good performing knives pretty inexpensively. You could probably even work up a set of knives for the same price as a single more expensive Japanese knife. Think of them as kind of the family sedan. It is reliable and gets you where you need to go, it just isn't as fast, flashy, or expensive as the neighbor's sports car.
With these type of knives you can have fun with making the sushi, and as you learn (and save more money
) you can grow into better sushi knives. The Fujiwara or Tojiro would just be a way to start without breaking the bank. The more expensive sports car can come later.