I spent a lot of my student's time searching the stock rom for Smart Prime 7.
So here it is!
HOW TO INSTALL:
1) Extract downloaded .zip file so after the extraction you will get 2 files (update.zip and .pdf file)
2) Put that update.zip file into your SD CARD.
3) Boot into recovery and select ,,UPDATE FROM SD CARD"
4) Select update.zip
5) Wait untill the whole install is done.
6) Reboot your phone and that's all.
note: this will delete all of your data!