Is an offline solution an option? You could install Arena and a blindfold chess font, then download and install an engine that can be dumbed down. That would work, as long as you don't care to play it on the internet.
If you're interested, I can give you links.
Hi, it is my first time posting anything here so I apologize in advance if I'm breaking any rules. Ok, I simply want to play blindfolded chess against a weak computer without compromise my rating. On 'Play' 'Live Chess' I can play blindfolded but my options on the computer strength are very limited and I couldn't play unrated.