best/CHEAPEST miniDV cam for track use?

[crosvs]

Hey everyone-

So i've got one REALLY GREAT prosumer miniDV cam (sony dcr-trv900 3CCD) that i've been using for 5 yrs; but i need one more camera for wednesday's thunderhill track day.

i want the cheapest possible while still getting usable footage lol ... i would like to have the manual override ability to set a ceratin exposure setting and to hold it there so it doesn't keep changing on its own as the lighting changes while driving. this i secondary though, and i do NOT want to pay more than $300 *MAX* seeing as how cheap cameras have gotten lately.

thanks

p.s. yes you will all benefit by the footage i record