Quantity   Component name
1 × Arduino Any 5v arduino with 6 digital ports
1 × MT8870 DTMF (about $2 on ebay) You can also use a DTMF chip to make the package smaller
1 × Relay module Optional depending on what you want to trigger. Relay can be used to open up a seaker
1 × Momentary push button Anything will work.
1 × misc wire, enclosure to meet your need.