I don't think there was ever a 7S-FE engine, 5S-FE, yes, 7S-FE... never heard of it.
As far as what engine came in 6th Gen Celicas, there was 2 engines available, the 1.8L 7A-FE, and the 2.2L 5S-FE. The 7A-FE-equipped cars were the AT200, the 5S-FE-equipped cars were the ST204, and the...