Hello

I have a Matrix-1000 (cream face model) and would like to replace the stock  solder leads   battery with a holder/standard coin cell. 

Does anyone know the correct holder part or has done this prior Can anyone advise what information/specs I need to order a battery holder for replacement. How to measure leads distance and correct voltage for instance. I have some experience in soldering and appears easy enough but my understanding of electronics and what I need specs wise is limited.