We present calculations of the invariant mass spectra of the Λp system for the exclusive pp → K + Λp reaction with the aim of studying the final state interaction between the Λ-hyperon and the proton. The reaction is described within a meson exchange framework and the final state Λp interaction is incorporated through an off-shell t-matrix for the Λp → Λp scattering, constructed using the available hyperon-nucleon (YN) potentials. The cross sections are found to be sensitive to the type of YN potential used especially at the Λ and Σ production thresholds. Hence, data on this exclusive reaction, which can be used to constrain the YN potentials are desirable.