Technically, if NEMA 7 is the only mark, no; it would need to be NEMA 8 to have an outdoor explosionproof rating. However, if it is marked NEMA 7 and one or more of the "outdoor" rated enclosures in Table 110.28 [2011 NEC] it would be acceptable.
With or without the terminal block, the enclosure does not need to be explosionproof.