How can second camera have different FOV than VR headset?

I understand the need for the camera FOV to match a VR headset, but is there any way to create a second camera with a different FOV or zoom?

I am trying to make a binocular effect in my app. I have a camera rig that is attached to the users head in VR, and uses the headset’s FOV and zoom 1. Then I have a model of binocular attached to the hand controller, with a second camera attached to the front. Then I made a plane as a render target and I can get the bino-camera image onto that plane. But right now the effect is kind of like looking at a phone screen with the camera on. That camera is locked to the FOV of the headset and I cannot find a way to make it show a zoomed in view. I tried making the render target plane bigger than the VR headset screen- which did show a big zoomed in view, except it was just pixelated because the resoltion is the headset resolution. And I would prefer to have the display be smaller than the headset so you still have peripheral vision (at zoom=1) anyway.

Any ideas how to create a second camera with a zoom rendering to a smaller plane in the scene while the headset still displays the normal FOV from its own camera??