My preference would be the WISC-V, given your child's profile, and the respective ages (publication dates) of the tests available to you. You may wish to bring the results of the WASI-II as well, since, if it was administered very recently, it could actually be used to substitute for the equivalent WISC-V subtests, which would bring the administration time down. And if not administered recently enough for that, the evaluator could at least use them as points of comparison. Either way, they will want to know about these prior test results.
The two achievement tests most closely aligned (co-normed or linked) with the WISC-V are the WIAT-III and KTEA-3. If you have reason to believe his reading comprehension will be unusually high--more than one or two grade levels above--you may wish to consider the KTEA over the WIAT, based on the design of the tests. Other than that, both tests should provide some good information.
