$150 a gallon is CHEAP. Good primer will run you roughly $130-$150 a quart with the activator. (4:1) If this is your first time painting a car I would highly suggest you buy better materials. They are much more forgiving and easier to spray than cheap stuff.
Honestly, I would block the car as it is right now and in the spring shoot it with a better primer and definitely a better bc/cc. You will find that the better quality paint you buy, the better the coverage will be. (which in the end evens out the extra cost, because you only have to use half the material you would with cheapo stuff) Not to mention the fact that its easier to shoot and is more forgiving (less curtains)
You may not believe me now, but when you get ready to shoot the clear coat you will understand.
Chromabase is an awesome paint. Its decently priced and covers well. You dont have to go out and buy House of Kolor paint (its about $350 a quart depending on the color) to get a good paint job. But on the other hand, you dont want it to look like Macco did it either