bah, that's freakin stupid though dude.
I don't understand why you can't simply put it off for a little while until you CAN do over $100
If you're gonna do watercooling, theres no point in doing it half-arsed.
The DD thing he put up is simply the D5 pump, not a prebuilt kit or anything.
Also, he never said $78 was a few bucks. It's not just a few bucks to him either. (If you couldn't tell, I know him in person, so I know how he is with cash to some degree), he was saying the difference between the bigwater and a decent setup that'd destroy the performance of a bigwater wouldn't be $78. You could make the difference as small as $30.
He gave you everything you need except for a pump for $70. There are pumps out there, that are a bit weaker than the D5 that would sell for $40-ish, and then your total is $110, only $30 between bigwater and a good setup that'd give way better performance.
You could even go 3/8" tubing......that'd STILL be a big improvement over the bigwater, and beyond that, it'd help that cheaper weaker pump to perform better.