In the past I have used both a radio shack and terk, I still own both. The terk was like $30 or so, and thus a little more expensive, not 100% if it's worth the extra cost but I didn't want to sacrifice too much with quality.
Terk info Sony I know makes one, and I am sure there are a ton of mobile ones as well. I noticed that once I was running 3 sets of cables the unit was very heavy towards the back and did not lay flat anymore, You would probably want to use double-sided tape or velcro, depending on your install. HTH
-Pete
