They are hardly just re-working the US-sourced equipment from the Shah's time, they're using uber amounts of effort on generating their own next generation technology:
The high speed mini-sub with supercavitating torpedo-
The supercavitating torpedo -
Low observable torpedo boats -
UAS/UAV/RPAS bombers -
Ababil recce UAS/UAV/RPAS -
Saeqeh low-tech fighter -
Chinese licensed J-10s -
