You CAN get her old & rare stuff, but not if you're not willing to work for it.
My advice is to find it via Yahoo! Auctions Japan. Most sellers there wont' ship overseas (in fact about 99% won't) so you need to go through a middleman. This can get expensive, but if you find a good deal on YAJ, it's not TOO bad.
Check with these middleman services; look at their fees & shipping costs and choose the one that's most reasonable to you.
www.shoppingmalljapan.com
www.rinkya.com
www.crescent-shop.com
www.celga.com
There are others, but these seem to be most popular.