Components, where to get them and a reference price. You may use compatible ones. The important thing is the display version. The bluetooth module may be another one or omitted (just adjust the PCB for another SMD chip, or just solder the RX/TX pins directly); the battery and charger models can of course be changed. The accelerometer is also optional, and for the display connector you may use a bigger one, or solder wire by wire...
Another option could be using a small Arduino board, like the Mini Pro, Nano, etc. Don't make my mistake, and make your life easy by using a board or a DIP chip, not an SMD one unless you have the tools ( SMD oven, etc. ).
|1||ATMEGA328P-PU||You can use a full Arduino like in the prototype|
|1||Crystal 16Mhz oscillator||For the ATMEGA chip|
|2||22pF capacitor||For the ATMEGA chip|
|1||DS1307||Real Time Clock chip|
|1||Crystal 32Khz oscillator||For the DS1307 chip|
|1||2,7 inch E-paper Display||Revision D, EM027BS013 from EmbeddedArtists||29 €|
|1||RN-41 Bluetooth SMD module||From Sparkfun||24.57 €|
|1||SPDT Mini Power Switch||From Sparkfun||1.42 €|
|1||3.7V Li Polymer Battery 103450 2000mAh||From Ebay||$ 4.14|
|1||Rechargeable Li-ion Battery Charger||From Ebay||$ 0.87|
|1||SparkFun Triple Axis Accelerometer Breakout||MMA8452Q from Sparkfun||9.42 €|
|1||Double Row Female Socket SMD 2x7 pins||Found a 10x10 connector on Ebay||2.72 €|
|1||Micro SD card shield module SPI||Bought in Ebay||$ 0.92|
|1||Kingston SDC4/4GB microSD card||Bought at a local store||2.5 €|
|1||Coin Cell Button Battery Holder Socket||bought in Ebay||$ 0.211|
Please note that some (or all) of the components could be found much cheaper in other (Chinese) shops; i put the ones i used just as a reference.