I've done a few of these... Yes they are mass produced, but "fake"? I know the components that are on they are real (I dug into one accidently and ripped one of the components off - so I played with it...). I suspect they designed a board of the size to fit around the tube, plus I doubt it was put onto any type of substrate. I've had circuit "boards" that are on flexible plastic backing - it's not uncommon actually... are those "fake" too?
The other part is any board when wrapped around a tube is going to have a seam. Even if by real you mean a rigid board that's been sanded or otherwise reduced to the point it can be wrapped around the tube, and then cut to size, that's going to have a seam too. You might be able to blend or hide it a bit better.
To the OP: I always order a stylus kit when I order the circuit board set and switch them. It works, but use light touches.