There are variety of options, but for the budget you are talking about you will need to think a bit left field.
I find it best to use manual mode on the camera and manual on the flash, so the flash needs to be stepped down by stops which can't be done on the cheapest flashes. However I have used some very cheap flashes hand used tissue and elastic bands to stop down the flash.
technique 1 - one flash on side of camera connected to hot shoe using a lead. place second flash in direction of subject at angle and it is triggered by a slave.
technique 2. get a Manfrotto
233 Flash bracket which is a long arm and place a a softbox on the flash. A small ball head on the flash helps. requires a dedicated flash lead and you get away with one flash.
technique 3 forget the hassle and get a ring flash