The work presents a novel method for fabrication of the high-quality ionizing radiation source (IRS), which is promising to replace unsafe commercial products based on (CsCl)-Cs-137 prohibited by IAEA. Spark plasma sintering (SPS) technique has been applied to produce dense ceramic and glass-ceramic matrixes from Cs-containing ((similar to)13.5 wt.%) zeolite yielding in non-dispersible cores sealed in the container of radiation-resistant steel (J93503, US standard). One-stage SPS regimes to provide high-quality product have been optimized: sintering temperature < 1000 C, heating and holging duration 13 and 5 min, respectively, pressure 24.5 MPa. XRD, SEM, EDX, BET, XFS and solid-state MAS NMR 133Cs methods prove exceptional physico-chemical and mechanical characteristics of the obtained materials, namely: density 99.8% from theoretical, compressive strength (similar to)477 MPa, leaching rate 10(-4)-10(-6)g cm(-2) day(-1). Results of the investigation can be promising for fabrication of the IRS cores on a large scale as done for similar Russian products RSL, IGI-C, M37C, GID-C.