+1 to the Tease blindfold, the wire inside means it will actually be light proof/she can't see what you are doing.
Have you guys ever done this type of play before? Have you ever used a sex toy? It might be too much to jump in all at once if you haven't done either before. A good way to start out is by blindfolding and restraining her then give her an all over massage. This will both relax her and provide amazing stimulation. Your touch will feel amplified to her, so no need to use the sex toy right away in order to have her enjoy the experience. This is also a good way to build trust, especially if you plan to go down the sub/dom route.
You can see the range of clitoral vibrators available here, you can sort by rating and check out the reviews of any that take your fancy:
You'll see the We-vibe Tango and other rechargeable vibes reccomended a lot, but they're both expensive and very powerful (especially the Tango). If this is her first toy, I'd go for something more gentle. This toy is non intimidating both in appearence and noise level, and the power level ranges from gentle flutters to strong (but not too strong):