Good lord....those are expensive beyond belief.
Do you have a bulk/wholesale nursery anywhere near you? A sheet of standard six-packs (i.e. 6x6 cells) will be somewhere around a dollar or less at places that sell them, and they can be re-used for many years before they crack.
They are hard to find online, though. I bought some extremely cheap ones from Amazon last year (my local nursery was out of stock & I was in a hurry).... they're very flimsy, but work ok enough, since I use them for giveaways (definitely not re-useable). Price seems to have gone way up in the last year, though:
In a pinch, you could easily make your own, too -- a cheap rectangular storage tub with holes drilled in the bottom, and some sheet styrene from the hobby store (to make dividers for cells) would work pretty well.