Hello. 

I need to buy a Nikon charger MH-25 for D7100 bateries in Siam Riep.  Does anybody know where can I find a big shop of photografy ? 

 

Thanks in advance. 

No idea, but you'll have more chance of getting a reply in the general Cambodia forum than in Cambodia travel so moving it there

There's only one camera store of any size in Siem Reap - it's near Rosy's Guesthouse on the junction of the Airport Road and the road that parallel to the river but one street back (can't remember what it's called); you'll know it from the big Fuji sign outside. It's good value and service there is great.