You won't regret buying the motors. I've got two of them as the direct-driven wheel motors on a robotic car thingie, it can be "driven" with incredible accuracy. I have also replaced the recycled ones I used to make the wall plotter with a pair of them. Their only real drawback of them is their speed.. but I can deal with it most cases, given the cheap-as-dirt price on them. You are going to end up buying a box of 'em from a wholesaler.. I paid less than twenty dollars for a box of eight including shipping, and am thinking about getting more. They are remarkably well made for their cost. The speed is due to the 1/64 gear reduction, so there's not a lot that can be done speedwise unless you do external gears or what have you. Paired with a ULN2003A premade board, all you need is a couple of jumpers to the control pins.
There is one quirk with them- if using standard Arduino stepper libs, the winding connections need to be declared in 1-3-2-4 sequence, rather than the expected 1-2-3-4. There's a few threads on this. Outside of that, a stepper with 2048 steps per revolution is amazingly useful...