I got 5 for around $3.60 shipped; thanks OP.
Yeah, the limit seems to be 5. You can circumvent this limitation by adding an additional adult account for free to your Prime membership though. Take a look at the "Share Your Amazon Prime Benefits" [amazon.com] section.
I haven't tried adding teens or children though; perhaps they can get around the maximum allowed purchased limitation too? I do know that adding a free adult account and a free Business account (Being a Cheap Basterd IS SERIOUS BUISNESS!
) works well for Prime parsimonious shenanigans...

2 hours ago
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