Difference between a IR photodiode and a IR receiver for break beam sensor

I need 8 break beam sensors but I just can't find any cheap ones so I decided I might as well make my own. I will have to use them for a coin detector, when the coin goes through, a voltage is sent to a pin of the Arduino.

I picked up some IR leds but I just don't know whether to pick IR receivers or IR photodiodes. The photodiodes seem more straight-forward but at the same time I am afraid of wrong readings because of visible light.

Meanwhile a IR receiver seems like the best option, light doesn't interfere with it and it's basically the same price.

Which one would you pick for this project?

I need 8 break beam sensors but I just can't find any cheap ones

I can't believe that.
Unless you think USD 1.4 is a large amount (and this is actually a pretty high price for what is on offer, I didn't want to spend more than 10-20 seconds on the search).

Photodiodes detect IR.
IR receivers detect modulated IR.
That's the difference. As a result the first is much more sensitive to ambient IR than the second.

Coin detector?
It seems you need some sort of photo interrupter.
Narrow beam IR LED and relatively insensitive photodiode in one package.
Tell us more about the setup.