This 2005 article has a slew of data about the PAEC. I think this paragraph is a decent summary:
…the PAEC has established most advanced engineering and manufacturing facilities in Pakistan. Its engineering set-ups, coupled with its technological developments, have achieved, progressively, a higher indigenization level and import substitution, and saved the much-needed foreign exchange. The higher level of indigenization has helped in bringing down the local production costs significantly as compared to prevalent international prices.