In terms of ability, school gifted programs may be geared toward the top two percent, which is IQ 130+, 98th+ percentiles, and some may be inclusive of high achievement, with test scores in the 95th percentile or higher. If your school doesn't have a GT program, what you seek depends on what your child seems to need that isn't being met by the school.
I'm not sure we have enough information. Do you see achievement scores in the high 90s on broader, nationally normed standardized tests? I'm not familiar the achievement tests you shared, but the stanines of 7 and 8 are not typically flagged for gifted extension (usually it's stanine 9, the 96th percentile or higher), but would be considered above average. Meeting benchmarks doesn't tell us if the child is above grade-level, if they don't assess above level. Cognitive ability testing would help you see if the child's ability doesn't seem to be matching their achievement, if you were seeking extension from the school.
Here's some helpful info on testing terminology, such as stanines and percentiles:
https://specialedonthebellcurve.wor...centiles-stanines-grade-equivalents-etc/And here is some information on what grade level equivalent means:
http://everyday-learning.org/grade-equivalent-score-fallacy/
