Google Cardboard Headset
VR for mobile is much less expensive than the PC, mainly because the headsets for mobile are basically just plastic and the phone does all the work. For the best deal, search the open market (but of course width of your phone should be written in place of "5.5 inches"). Some take a very long time to arrive, so check the estimated arrival time and make sure you're fine with that.

Game Controller
Whichever one you use, it needs at minimum:

• Two joysticks
• Enough buttons to map these: A, B, X, Y, Start Select, L, and R

I do not recommend MOGA due to the fact that the drivers eat up a lot of hard drive memory (which is easily cleared), but if you really can't afford the controller I recommend, visit MOGA setup page.

I have tested these games on a True Depth 3D Controller and they work very well.
I'd search the open market for a good deal, so if you do, look for this: