[SiriusHardware]

Also clock timing crystals are much easier to find than specific obsolete ICs, although you need to pay attention to the capacitance figure (if any) specified in the data sheet and find a crystal with the correct spec otherwise it may run noticeably faster or slower than it originally did. I don't know if the circuit under discussion has a variable trimmer capacitor for fine adjustment of the timing.

If you have a comms receiver which covers the 4.194304Mhz frequency of the crystal try tuning around that frequency, ideally in SSB or CW mode. If the oscillator is running you will hear a steady note or whistle when you tune close to the right frequency: It should disappear when you remove the battery from the clock.