I think they compress pretty good. I know menards, tractor supply and other regular hardware stores handle it in the wood stove area. It is a common repair part.

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This is the flat stuff I think you are talking about. I use it to seal the gap between the door and glass on my wood furnace.

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This is the fluffy rope. It is actually made to compress and fill odd gaps in doors. Other suppliers will include a cement with the "door kit". Sorry but I just hate it and it just does not seam to work. You can push it into the gap area and make it pretty flat. And you might have to get the gasket kinda/pretty wet with the silicon to make it stick to the stove and the gasket. The gasket is fiber glass not much wants to stick to it. (wear gloves, it will make cleanup easier)

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And, if you do use the silicon with a fiber rope, maybe use food plastic wrap between the door and gasket, so when you shut the door (most silicons set in a couple hours), it won't stick to the door when you open it.