Popup Camper Poles

I'm looking for the four interior poles (2 ea side) that go diagonally in each corner of the canvas above each slide out bed. They hold each end up so the canvas doesn't collapse. I believe they measure 48" (4 ft) each.

I am also looking for the exterior slide out supports that mount under each bed and anchor to the frame. I have rigged something up but would prefer to use the intended design. Thanks