Any high backed boosters that would fit a 7 year old?

[scrapquitler]

The high backed booster our 7 year old is in right now is an old 5 pt harness one that converted to a backed booster. However, it no longer fits her right as the shoulder strap isn't above her her shoulder anymore, so she has outgrown it.

Does anyone know of a different high backed booster that would fit a 7 year old? She is 50 lbs and 48 inches tall.

Thanks!

My 8 year old uses the Graco Turbo Booster. He is about 55" tall.