I have read a ton of research on google and found that the best option is from amazon.com
I also got very fast&free shipping from amazon for more than 50 usd items.

Kingston Technologies 1GB DDR SDRAM Desktop (KVR400/1GR)

Monday, 15. March 2010. 10:39 by memory sdhc

Kingston Technologies 1GB DDR SDRAM Desktop Memory (KVR400/1GR) List Price: $30.47
Want more discount? get it here -> compare price
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Kingston ValueRAM KVR400/1GR is a 128M x 64-bit (1GB) DDR400 CL3 SDRAM (Synchronous DRAM) memory module. The components of the module include sixteen 64M x 8-bit (16M x 8-bit x 4 Bank) DDR333 SDRAM in TSOP packages. This 184-pin DIMM uses gold contact fingers and requires 2.6 V. The product comes in the packaging for retail sale and provides instructions for installation.
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