Solutions for minimum focus distance problem?

Hi all,

I've recently invested in a table dolly for my Canon 7D & Tamron 17-50 f/2.8 and Canon 50mm 1.8 lenses. I'm trying to do a few video shots of my things laying flat on the table, but a problem I'm having is that I can't seem to be able to focus on what I want to focus on because unfortunately, my camera and lens are too close to the subject.

I'm trying to get a closeup as the dolly moves in, but even on a 4" pistol grip on the dolly raising the DSLR, it's still not high enough.

Now I know some may probably just suggest using some hardcover books stacked on top of each other (with a large enough surface for the dolly to travel), but I was wondering if anyone had any other suggestions as to how I could move the camera high enough from the subject, allowing me to focus, but hopefully not too far back that I don't get the closeup that I need.

I'd like to avoid the stacking of books if possible, but if that's my only solution, then it's okay. I'm on a very low budget and can't really afford macro lenses.

If I've lost anyone, you can reference The Verge's Pocket App review at around 0:08-0:11

Those closeup shots of the iPhone as he uses it is similar to a shot I'm trying to achieve.