[@Athol]
If I were to give you a time period, I would say somewhere between the first and second industrial revolution. Cars are a thing, electricity is becoming common, things like steel is becoming mass produced, things like that. Think old technology in a progressive society. R&D towards economy and state of living was more emphasized than technological advancements. With the spirit users in play there is a large focus on the supernatural in society. 

Hopefully that gives you some ideas. I hadn't really thought too hard on tech so I kind of just threw that explanation together. Sorry if it's a bit vague.