Angelina Jolie

Where can you get a R4i, AK2i, M3i or dstti card from a trustworthy website?

I’ve read so many answers on this explaining that some say the AK2i card isn’t good, or R4 company shut down a year ago, and there are many clones. blah blah blah (hehe) but I don’t know which I should believe. But, I’d still like to know what website can I trust to buy those cards and is within the US, not the UK (because they might lose it overseas). and WHICH I should use. All comments accepted!!!! PLEASE HELP!!!
p.s. i have an dsi
and THANK YOU ALL!!!!