A frost plug is a frost plug, the only real difference is the size.
To bang the old 1 out I use a screwdriver (without a handle) and drive it on the lip until it starts to rotate in the hole.
Then I slip the screwdriver behind, and pry it out.
Those frost plugs that your talking about are an expansion unit. Tighten the bolt and they expand in the hole.
Your local parts store should have the size listed, and get you what you want