Can we state that we are in conformance with the IIA's standards if we do not undergo an external QA or independent validation, but have a contract to have one performed after the end of our five-year cycle?

No. An internal audit activity must demonstrate conformance with The IIA's Standards before it can state that it is in conformance. Simply having a contract to perform an external quality assessment after the end of the five-year cycle is not sufficient to demonstrate the conformance with the Standards. Therefore, the internal audit activity cannot state that it is in conformance with the Standards.