Lava Louie kit question

[amy m]

I have a Lavalite brand lamp which flowed for about a week, but now the lava just sits in one big lump at the bottom no matter how long it runs. I have been reading all the posts here from people who replaced their lava with the Lava Louie kits and the results look amazing, so much better than mine ever looked. Does anyone know how much Lava I would need to get for my size lamp? I think it's the size right under the Grande, I don't know the liquid measurement, but it's 16.3 inches tall. Also, mine has a cap on it like a pop bottle, does anyone know where you can order a replacement? Any advice is appreciated!