Amazon.com: Koolertron Rear View License Plate Backup CMOS Camera: Electronics
Its wired - sorry, should have specified. Since you mentioned a decent wired version too. I plumbed the wires through my pilot light hole and hooked it into my reverse light for a trigger, and it pipes the AV signal into my head unit (double DIN touch screen). For the price, hard to go wrong. Has superimposed "straight" lines too.

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TC
Current stable:
- 2004 Mazda RALLYWANKEL
- 2007 Saturn sky redline
- 2004 Explorer...under surgery.

Past: 135i, GTI, 300E, 300SD, 300SD, Stealth