Yes, there are several theoretical frameworks and models that go beyond the particles predicted by the Standard Model, including those that predict the existence of heavy elementary particles beyond the Higgs boson and top quark.
Supersymmetry (SUSY) is one such theory that introduces a new symmetry between fermions and bosons. In SUSY, each particle in the Standard Model has a superpartner particle with different spin statistics. These superpartners are expected to be heavier than their Standard Model counterparts and could provide solutions to some of the outstanding issues in particle physics, such as the hierarchy problem and the nature of dark matter.
In certain supersymmetric models, there are heavy particles called sparticles, which include the superpartners of quarks, leptons, gauge bosons, and the Higgs boson. The masses of these sparticles are not constrained by current experimental measurements and could be significantly higher than those of the known particles in the Standard Model.
Another theoretical framework that predicts heavy particles is extra-dimensional theories such as Kaluza-Klein theory and string theory. These theories propose the existence of additional spatial dimensions beyond the three we are familiar with. Within these extra dimensions, there can be particles called Kaluza-Klein states, which are excitations of the known particles in the Standard Model. The masses of these Kaluza-Klein states can be significantly higher due to the compactification scale of the extra dimensions.
It's important to note that while these theories predict the existence of heavy elementary particles, experimental evidence for them has not been found yet. The Large Hadron Collider (LHC) at CERN has been searching for signs of these particles, but so far, no conclusive evidence has been observed. Nonetheless, the search for physics beyond the Standard Model continues, and future experiments and observations may shed light on the existence of heavy elementary particles predicted by these theories.