Hi Adam,
welcome to the forum.
It is most likely that there are no datasheets for discontinued relays.
Please specify voltage and current for the relay coil and number of contacts, e.g. single pole - single throw, single pole - double throw etc., as well as the switching power rating
A dimension drawing would also be very helpful.
With these information it's relatively easy to find a relay fitting your device without big scale modifications to the PCB.
Boncuk