Hey Alexander! So Sony has ways to buy parts from them or through their supply chain. You can either give Sony a call and ask or visit their supply chain to look for the part. Here are the links: Sony USA Replacements Parts Encompass Supply Chain Sony UK Replacement Parts Hope you find the parts you need!

Hey Alexander! So if you have dark spots on your pictures, you probably have dust on the mirror. You can simply use a clean cloth (I recommend a micro fibre cloth to be safe) to wipe the mirror and get all the dust off. To avoid getting dust on the mirror again, Sony has a list of things to do to take care of the camera (Sony: How to Clean and Maintain Your Camera and Lenses) Hope this helps!

Hey Dima! First, see if it is just dust or something is on the screen. You could use a cloth to check. If that doesn't work, unfortunately you might just have to replace the mirror. Replacing the mirro does require almost completely disassembling the camera though. -Samuel Lee