Litton MobilVu
Here is one:
http://cgi.ebay.com/Litton-MobileVu-Rugged-Mobile-LCD-Touch-Screen-Display_W0QQitemZ320151683752QQihZ011QQcategoryZ3698QQssPageNameZWDVWQQrdZ1QQcmdZViewItem
I thought I bought mine for just over $100 though.
The only complaints I have are: the touchscreen kinda sucks. You're better off with some type of mouse, trackball or something else.
It is also heavy at 7 lbs, but also very rugged.
There may be other solutions with a few more $$$
I think some of the GPS / DVD in-dash displays, such as AVIC from Pioneer accept analog video input, and are bright. one solution would be to convert VGA to analog and feed it in. You'd lose some quality, but for what you need, it won't matter.
The other thing about MobileVu, resolution is at 480X600. Make sure your computer can go that low before you buy.
Hope this helps.