SainSmart 3.2" SSD1289 touch screen: $17.59

https://www.amazon.com/SainSmart-3-2-Inch-SSD1289-Arduino-Raspberry/dp/B008FWSG3S

63 6mmx6mm momentary pushbuttons: $2.23 (for 100)

https://www.amazon.com/Yonger-6x6x4-5mm-Momentary-Tactile-Button/dp/B01L95LP8K

Joystick: $6.99

https://www.amazon.com/KY-023-Joystick-Sensor-Module-Arduino/dp/B01FDGUC58

on/off switch (SPDT 3mm): $4.33 - check its current rating though

https://www.amazon.com/Uxcell-a12013100ux0116-Position-Vertical-Switch/dp/B007QAJUUS

... or via sparkfun, $0.75? - .2A @ 30vDC; should we get a beefier switch?

https://www.sparkfun.com/products/9609

battery holder: $4.35 (for 10)

https://www.amazon.com/yueton-Battery-Storage-Holder-Single/dp/B013DUOJV4

batteries & charger: $13.99

https://www.amazon.com/EBL-lithium-Rechargeable-Batteries-3000mAh/dp/B0129F9BXK

standoffs, black, 25mm x m3; $9.72 / 100

https://smile.amazon.com/M3x25mm-Female-Thread-Standoff-Spacer/dp/B015K4AT6K

PCBs (both)

printer/serial port?

wifi?

wiring for touch screen?

voltage divider for battery sensor: resistors + cap

header for the LCD PCB
standoffs for the LCD PCB
M3 screws

25mm M3 male/female brass standoffs: $7.01 / 20 ($9.52 / 100)

https://smile.amazon.com/M3x25mm-Female-Thread-Standoff-Spacer/dp/B015K4AT6K/ref=sr_1_2?ie=UTF8&qid=1491143911&sr=8-2&keywords=pcb+standoff+25mm