Matt, have you seen this: http://www.fish-street.com/cart/co2_test_kit? If the shipping cost isn't an arm and a leg, this is a price that is very hard to beat. But, someone here with extras would certainly be more likely to be quicker and more dependable.
Thanks Hoppy. I checked it out and the price to have two of them shipped was only $16.00. Not bad. I may just go ahead and order them. I really like those new ones that greenleaf has that have a reference solution vessel also, but I find it hard to dish out $40 for one.
The problem with buying from some international site is the wait time. It's rediculous, I bought from Aquaspot world which I believe is in Singapore or something like that and it took 3 weeks to get to me. If you don't need it right away i'd order from the above said site, if not, i'd definitely pay a bit more to get them sooner.