Looks good. I found the datasheet at:

http://www.semiconductors.philips.co.../PCF8583_5.pdf

Also looks like you will need a decent scope to be able to evaluate the cap needed to keep it accurate. Or simply play with different caps over longer period of time to see how well it keeps time. The datasheets say +- 5 minutes over 1 year should be achieved.

I could not find somewhere to get it in N.A. easily though. I guess you are in the E.U.?