Quantity   Component name
1 × Pi Zero w/ imaged SD card Get it from the usual sources.
1 × LIR2450 battery with solder tabs I got mine from batteryspace.com ,part LIR2450-V1. Shipping is expensive though.
1 × double sided foam tape Around 1/16" thickness.
1 × bits of wire 30 gauge wire wrap wire is what I used.
1 × 3 pin male header plug with leads Solder wires to a 3-pin header and add heat shrink. Or get creative!
1 × TP4056 Li-ion charger board Get it from the usual Chinese suppliers. The one WITHOUT built in battery protection circuitry.
1 × 12K 0603 surface mount resistor 10K will also work. You should be able to find one on a scrap circuit board.
1 × 1S Li-ion protection board, rectangular 28mm long, get it from the usual Chinese suppliers, or salvage from a dead cell.
1 × .96" white IIC 128x64 OLED display module Get it from the usual Chinese suppliers.
1 × SPDT slide switch, .1 inch pin spacing Get it from the usual Chinese suppliers, The smaller the better.
1 × 3 pin female header plug with leads A cable and plug from an old servo works nicely.