Ay there's the rub, I can't find the coil resistance, but have since learned that other similar relays have a coil of 750 ohms, so my fears are somewhat allayed. The CSMIO-IP/S has opto isolated VNQ860 as the output stage, and they appear to be diode protected, but I would put a diode local to the relay anyway.

Cheers and thanks for your input on this question of output :)