FRYS B&M only.. YMMV
Pioneer Rear-View/ Backup camera ND-BC2 $49.98 / Pioneer ND-BC20PA $74.98

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Best deal i have found so far on these. Sells for around $200 retail.

Features: ND-BC2

* Wider Viewing Angle: 135 Degrees (Horizontal) and 100 Degrees (Vertical)
* 1/4" Color CCD with 270,000 pixel resolution (491 x 512 pixels)
* 1.5 ~ 10,000 Lux Automatic Luminance Control (includes automatic low-light lux mode for higher detail and contrast in low-light conditions)
* Compact Camera Unit: 1" (W) x 1" (H) x 1" (D)
* Composite Video Output (6m cable included)

Features: ND-BC20PA

* Adjustable (Normal/High) viewing angle for easy assessment of parking space width and depth
* Lens Correction for undistorted rear view image
* Camera position compensation rotates the image for optional rear view without changing camera position, even if the camera is not installed in the middle of the rear and aimed horizontally.
* Wider Viewing Angle: 135 Degrees (Horizontal) and 100 Degrees (Vertical)
* 1/4" Color CCD with 270,000 pixel resolution (491 x 512 pixels)
* 1.5 ~ 10,000 Lux Automatic Luminance Control (includes automatic low-light lux mode for higher detail and contrast in low-light conditions)
* Compact Camera Unit: 1" (W) x 1" (H) x 1" (D)
* Composite Video Output (6m cable included)

None in SoCal.

Once, while sitting in my driver's seat, I watched someone as they slowly, casually backed directly into my car. They were trying to back up while relying on one of these cameras.

Don't waste your money on these things. People have been driving for 100 years without them, just use your eyes and be aware of your surroundings.