My latest 8GB
Class 4 SanDisk MicroSD cards cost $2.99 each, shipped
from a US seller and they arrived in 3 days from the order. No
adapter, of course.
Are you sure it's a SanDisk?
Here in Brazil you find phony SDcards everywhere. The rule is "if it is
in a package, is original" and seems to be true. But the price (in USA)
seems not to be so far. I bought a 16GB card (for my Dreamcast) some weeks
ago for R$ 35, which is Us$18. Considering it is double the capacity, and in
Brazil, the land of huge markups and incredible taxes, I doubt in USA this
card would cost more than $6-7. Ah, mine came with adapter.