Felix,
I'm not really sure what you say is wrong with the ones from Lowes for $24.95? All of the ones I bought from Lowe's had both a large foam block in the body of the case, and a piece of foam in the lid too. The cases will hold two transmitters with no issues at all. Even if it's missing the foam in the lid, you can pickup a piece of foam from Wal-mart for a buck or so. If you check around you can usually get foam for free. Ask any computer shop, they usually have it coming out of their ears (trust me, I know. I own a computer shop). They'll usually give you all the foam you want for free if you ask for it.

Ken