Can we install the stock ROM for P3110 on P3113? (7 inch Galaxy Tab 2) The P3113 model of the Galaxy Tab 2 hasn't yet received the Android 4.1 (Jelly Bean) update.

Is it possible to install the stock ROM for the P3110 ROM (take from sammobile) on the P3113 device?
You can install it, but not everything will work properly. Most things should work, but not all.

Read the forum / thread from where you are downloading the ROM. If you are okay with a few things not working you can get it. Otherwise, you might want to wait till a ROM is ported out for your particular device.

You can read the XDA Forum thread What's the difference between 3110 and 3113? to know what people have got working and what didn't work for them.