I am looking for pointers on headsets (ie headphones and integrated microphone) as this is an area I have not dealt with before.

My daughter works from home (in NZ) for an Australian employer.  Said employer uses outsourced services to place elderly Australians into aged-care facilities.  Their office uses cloud services and is entirely based on website and voice through  Windows-based hardware (ie desktops and Laptops).  They receive inquiries by phone and website, and use phone calls extensively in the placement process.  There are no in-house servers so I assume phone calls are all based on a VOIP service.  Every employee can work from home if required.

The need for a replacement headset comes from occasional difficulties with callers claiming poor voice quality.  Occasionally my daughter replays calls and has noted very poor voice quality on the recording.  The headset she uses was a Harvey Norman special when she bought a recommended laptop, and connects through a USB port.

Headsets are used for confidentiality and noise reduction.  The need in a microphone is for a device that is very close to the mouth and picks up voice from very close proximity with good voice sound quality but at the same time not picking up nearby sound such as background noise or others talking nearby.

Price is a consideration but the priority is quality.  I would appreciate any references to this type of hardware.  I can then use this as a base for ongoing research if need be.  NZ-based suppliers prefered but not essentiual.