It seems that in teaching math to young students, educators incorporate math games using dice numbered 0-5, and so these dice are often available where teaching aides are sold. I decided to buy from a few different places to compare the results.
The first place I shopped was, http://great-extensions.com/ . This site was possibly the most convenient. I simply scrolled down through the dice page until I found the dice I wanted and clicked, add to cart. This took me directly to a paypal checkout and I bought my dice. The dice were shipped standard mail in a thick envelope and arrived promptly.
These dice have rounded edges and numbers in a sanserif font. They are $1 each. I ordered 6 of them paying $6.00 for the dice, .90 shipping and .51 tax for a total of 7.41 or 1.24 each.
Next I tried, http://catalog.mathlearningcenter.org/ . The math learning center was not quite as convenient. I entered the order online and then had to call with my phone to give a live person my credit card information. These dice came 5 to a pack with a flat $5.00 shipping. (Shipped UPS)
Five dice cost $3 here but shipping charges are rough on a small order. I ended up ordering 2 packs of five bringing my price to $1.10 per die with shipping, which was cheaper than the other place, but only because I ordered 10. These dice have squared edges and a serif font.
Finally, I was going to order from http://www.boxcarsandoneeyedjacks.com/ . They pictured dice with different colored numbers. These were .75 each and I placed an order for 10 of them. But then my order was rejected stating that I had not met the company's minimum shipping requirement. "Phewey!" I ended up not ordering the cool dice with the colored numbers.
Which is just as well. I have decided that I don't like the rounded edges or the sanserif font as much as I like the squared edge and the serif font. So, the dice from Math Learning Center end up being my favorite. I bought enough dice to give a pair to everyone in my Tuesday night Five by Five game which will make a nice surprise for tonight.