WTB: 4" DC exhaust Silencer

[05Tib]

I need silencers for my exhaust. Dual Canister, each tip is 4 inches. anyone have silencers or know where i can get them? all i can find are 3" silencers and im pretty sure mine are 4". Here is the link to what i have

http://www.aempower.com/ViewProduct.aspx?ProductID=948#