Here are the components you will need.they can all be bought from Amazon and ebay and if you shop around you should be able to build the whole module for less than $20.
1.DFplayer mini.
this is the board that makes the sound.it has an onboard microSD card reader and pins for input and output.If you want to know what each pin does there are manuals describing each pin and wiring diagrams to help you.There are also a ton of youtube videos showing how to connect the dfplayer to an arduino or add buttons.
Here is the datasheet;
http://www.picaxe.com/docs/spe033.pdf
2.MicroSD card.
This is used to store your sound clip. A 16G card will give you hours of storage space.
3. JST 2 pin connectors
these connectors are used to connect the dfplayer to the battery pack and speaker.
you could skip these and solder the wires from the battery holder and the speaker directly to the dfplayer.
4.Speaker
I set up my module to play mono clips so I just needed one speaker.This speaker produces really nice loud sound.you can use another speaker if you wish, but it should by 3watt 8 ohm speaker. I got mine form Amazon
https://www.amazon.com/g...title?ie=UTF8&psc=1
5.Battery holder.
I used a 3 AAA battery holder with a switch.The dfplayer needs 4.5-5V dc power.Anything over 5 v will damage the board.
If you need to put the sound module in a place where it cant be accessed you can put a switch between the battery holder and dflplayer and mount the switch somewhere accessible.
6.Box.
I made a box to put the dfplayer in.thee is a lot of room inside the EVA pod that I made this for so I 3d printed a box to keep the dfplayer from getting dusty.
darbyvet attached the following image(s):