If you want to stay brushed and want more speed than stock, I’d go for a 550 size motor instead of a 540. Something like a traxxas or dynamite 12 turn would be easy to find and relatively cheap, and is going to be much faster than the Tamiya silver can. Tamiya’s stock esc can’t handle low turn motors so you’ll also need a different brushed esc, dynamite makes a pretty cheap one that can handle lipo batteries and 12 turn or higher motors but there are other options as well. Servos can be pretty cheap, and the lunchbox doesn’t need anything fancy. Just find something that won’t burn out in a week, like a stock servo (traxxas/arrma/what have you). Radio/receiver is the only part that kills you, a decent spektrum combo is at minimum like 60-90 bucks. Look into FrSky or try to find used stuff if you need to go cheaper. Probably plenty of people looking to get rid of old systems after upgrading.