I’d recommend a simple vacuum pump off of Amazon. I’d recommend ~6 CFm and 1/2 HP. We use a Mastercool Pump, but I am sure there are other good ones.
There isn’t a specific abrasive pad that won’t take down carbon, but there are methods for minimizing the ware on the carbon as you take down filler material.
1. Tape off the carbon that you don’t want to get sanded.
2. Use the highest grit possible to achieve the surface finish desired.
3. Use good filling techniques to minimize the amount of additional sanding required.
We purchase materials from many different vendors, but for an individual looking for small amounts I would recommend Fiberglass Supply, Composite Envisions or Soller Composites. They are located in different parts of the US, so you can save on shipping picking the one closest to you.
For higher quantity purchasing I would suggest Composites One.
There are a handful of different flow mediums, although the most common are the “green flow” and “blue flow”. Green flow is oriented linearly and the blue flow is random.
More important than the infusion mat used is where it is applied. The best location for the infusion mat is actually within the laminate, but this means it will be part of the final layup. In some cases this is okay, but more often than not you won’t want it included. To avoid this, the flow medium must be placed on top of the release cloth. I recommend using a layer of perf-bag between the peel ply and the flow medium so that it will release more easily. It is also very important to apply the flow medium over the entire part so that the resin saturates everything.