It sounds like plain-old roller bearings will work for your application (or maybe needle bearings, depending on how much precision you are looking for).
McMaster-Carr is a great supply company for inexpensive bearings. I've purchased quite a few small bearings for the odd project from their website, and have yet to be disappointed. Bearings of the size you're searching for tend to run less than $15 each (sometimes much less than that).
The McMaster website is also extremely user-friendly - just type in "bearings" in the search box and it will bring you to a page where you can pick and choose which features you are looking for (mounting flanges, ball vs. roller, size, etc).
Here's the website: