I doubt if there's any such thing. You might consider the peak to be too flimsy but it's made that way so that it deforms in an accident. If you can find a stiffer peak, you'd probably need to modify it to fit.
The alternative is to stiffen the existing one or use weights to change the resonant frequency. Some folks stick lead wheel balance weights on the underside. This is particularly the case with Arai Tour X peaks.
I'm not too keen on adding weight to anything so I use a strip of screen edge trim on the leading edge of my Tour X peak to stiffen it. The other thing which helps is to insulate the points at which the peak touches the helmet shell. Again, on my Tour X, I've made rubber shims to fit under the points of contact. On my Shoei Hornet, I cut open a Scottoiler delivery tube and slipped that over the edges of the peak where it touches the helmet shell.
I've also found that using a Laminar Lip on my screen makes quite a difference, as does wearing filtered earplugs rather than foam ones.
HTH
