any sort of RTC should work, you'll need to alter your programming for differences in how the clock presents time... I believe the 1307 is hhmmss and mmddyyyy both in BCD format ... others are pure binary
so visit www.maxim-ic.com and download the datasheet for the 1307, and then compare it to RTCs that you can obtain in your area.
their site didn't help much i must say, all i wanted was a simple routine to get time, and all i got was mangled code connecting to keypad, rs232, lcd with 4-bit interfacing, bla bla bla, and i surrendered.
Yup, visit that site and try to request sample for ds1307. If you're lucky, they will send your request to your address. You can also request other ICs and RTCs there.