You can use the Offline Store Locator and visit a verified electronics shop near you or directly buy these components online using the links below.
Just replace normal wheels shown in the video with mechanum and you are all set!
ESP8266 - https://robu.in/product/nodemcu-esp8266-v3-lua-ch340-wifi-dev-board/ https://robu.in/product/l298-based-motor-driver-module-2a/
L298n (motor driver) - https://robu.in/product/l298n-2a-based-motor-driver-module-good-quality/
Motor (*4WD) - https://robu.in/product/300-rpm-bo-motor-straight/
Mechanum Wheels (4) - https://robu.in/product/80mm-a-mecanum-wheel-compatible-with-6-7mm-coupling-pack-of-4-yellow/
18650 battery *3 https://robu.in/product/orange-icr-18650-2000mah-25c-lithium-ion-battery/
Battery holder https://robu.in/product/black-plastic-storage-box-case-holder-battery-3-x-18650-cell-box-without-cover/
Battery Charger https://robu.in/product/eu-plug-universal-battery-charger-for-18650-16340-14500-li-ion-rechargeable-battery-charger/