Soundhole Feedback Buster for OM-40?

[ReverendRuckus]

 
Recent Larrivee owner & first-time poster here...looking for a recommendation on a soundhole feedback buster for my OM-40.

I have an amazing OM-40 with an Australian Red Spruce top that I put a K&K Pure Mini Pickup in. I love the plugged-in sound (surprisingly, I'm not usually a fan of plugged-in acoustic sound) but I get some feedback when hitting low strings (usually in G shapes even when capoed). I bought a feedback buster from D'Addario but when it arrived it was too big. Does anyone know of a soundhole feedback buster that fits the OM-40?? Thanks!

[unclrob]

If I'm not mistaken thereis a smaller version or you could go old school a piece od poster board with a design on it and some double sided tape from inside the guitar.