The Greenwich Instruments GR nvram ICs are available direct from the manufacturers at Greenwich Instruments. They are in current production and the ideal general purpose chip to store data with an in-built lithium power source can retain data for up to ten years or more.
The whole family of 16k (GR281), 64k (GR881), 256k (GR3281), and 1Meg (GR12883) devices can be found at http://www.greenwichinst.co.uk
