it depends on how many people are demanding, and how many they are producing. If he only makes a certain number of scan gauges, and a whole lot of people are demanding them, then the price would go up typically.
However, if they just choose to make more scan gauges the price would stay the same, and they would just sell a higher quantity. In this case they could reduce the price and still make a decent profit since they will be making more sales over all.
I remember seeing that they had sold out of scan guages and that they weren't going to make any more for 2005. Although that is most likely due to the newer version being phased in.
My old one fits ok on the dash but is just a little too small to see and it seems to be running all by itself sometimes when I get in the car. Would give me a spare one to check other cars with too and a smaller one will fit on the dash better. The other thought I had was to cut down the old box to fit better and put some dimming in it to worok off the dash lighting control and maybe allow sunlight into the back so it can be viewed better on sunny days.