https://docer.pl/doc/xvv55s0
The original relay is an old SM-1 type (three-phase, 16A contacts, 220VAC coil). The last pages of the manual - see spare parts tables. Today it's called "stycznik TSM-1", search for it on google.
But, you can use any three-phase relay, minimum 3x16A current (25A is enough) and 230VAC control coil.
Good luck!
PS: I like translator, too
