So i was browsing to find a nice clock on maxim-ic.com Maxim has some new RTCC with internal oscillator which minimises part count on the pcb but the cost is like 7,50$ each, that raises production costs. I could also use DS1307 which is a standard RTC with I2C, the cost is about 2,90$ each.
While i was browsing microchip i saw the MCP79410 which is by far better than the DS1307.
It's cheaper, about a third of the DS (0,80 or 0,90$) and it also is a direct replacement. Pin compatible, same start and stop conditions and even the memory map is the same PLUS some more features like alarm clocks and timestamps.
I ordered 3 and now designing a 100 x 160 mm dev board to integrate them on my system. Seems like a better and cheaper way for production purposes.