I manage call centers as part of my job. I have a KPH30i that I've used for conference calls from my cell phone. They are lousy. They bleed so much noise that the phone picks up the output for the earcups. For this use case, you get what you pay for.
I am still just baffled that your employer is not at least giving you a 'recommended' list of devices.
If you're looking for something cheap-ish....you can go with this Logitech set that will probably be OK for gaming purposes.