Official Sony PlayStation Vita Memory Card 64GB (Vita) - £52.22
9,411.00 JPY = 48.4442 GBP XE.com
Can pay in GBP
Economic Registered - Delivery within 2-3 weeks with tracking number + insurance 4.86£
Economic - Delivery within 2-3 weeks without tracking number and without insurance
edit: 20.11.2014 price dropped by over £4 - The price may fluctuate up or down slightly depending on the exchange rate. Many people have now used and recommended this site, just see the comments below :)
06/05: £54.75 + £1.63 JP Post Eco (2-3 weeks) = £56.38
EDIT: Changed shipping method to JP Post Eco (2-3 weeks) as it's the cheapest available. Just go with the service you want, there are quite a few different options. Good company, got a white Vita and a 64Gb card from them --- Price may vary by a little as it depends on the exchange rate at the time, which payment method you use and their prices also go up/down by a pound or two all the time. (PP exchange rate is probably different to your CC).
£60.23 here http://www.yesasia.com/global/playstation-vita-memory-card-64gb-japan-version/1034043241-0-0-0-en/info.html in case you'd rather order from them.
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