Ordering in Ni-based superalloys is the crucial process controlling the development of the characteristic two-phase microstructure and subsequently the mechanical properties. Disordered systems containing up to six alloying elements typical of advanced Ni-based superalloys were modelled in this work. Their ordering at elevated temperatures was simulated using a Monte Carlo approach with phenomenological Lennard-Jones pair potentials. Selected atomic configurations differing in the degree of order were subject to further studies of elastic parameters. Hydrostatic deformation and uniaxial deformation along high symmetry directions of model crystals were simulated. Molecular dynamics was used to relax local atomic positions in deformed crystals. Changes of elastic parameters due to ordering in face centred cubic lattice are discussed.