I'm thinking a quadruple stars system where a binary star system orbits another but more massive binary star system is probably fine, however so far I never encounter binary planets orbiting triple star system. Would it be realistic to find one out of billions and billions of galaxies and stars?
Stable structures have a hierarchical binary structure.
However, not every slot has to be populated.
So, the closest thing to what you describe would be (planet,(star,(star,star))) (see figure e).
So technically you would say the planet is in orbit around a binary system, and it happens that one of its members is itself binary.
Beyond that, you need the spacing to be such that the binary components are compact and/or distant enough so the lumpiness is not a problem. That means each level in the hierarchy is much larger. Then, the neighbors and galaxy at large and galactic tides cause disruptive effects.
So, the planet might not be stable in orbit around the distant stars, but get grabbed by other passing stars or perturbed by outside forces.