I think some suppliers will sell you a piece of a carpeting set, ask; someone mentioned this before.

On the shelf, I don't know if heat, age, or what caused this, or if it was this bad in the first place, but that wood pressboard is the cheapest piece of cr** I have ever seen; when I cut my speaker holes (slightly larger, they were there already) with a jigsaw it disintegrated the wood more than it cut. Seriously, maybe this is a safety feature - the wood disintigrates on impact instead of becoming a projectile? My $0.02, I'd cut another piece out of better wood. If I get in an accident and survive I'll probably be suicidal (my fault) or in prison (their fault!).