John Saunders at NYC CNC / Saunders Machine Works has been building a full size Johnny 5. He outsources a lot of the parts to the maker community, which made for a lot of great YouTube videos. It ground to a halt with COVID, but they’re starting up again to finish it.
I don’t like the teleop-keyboard, so I’m glad I got the joy node working. Depending on how much driving you anticipate doing might be worth trying it. I already had a controller from an older project (I’m not a gamer), but you can get a generic Xbox controller for < $20 on Amazon. You could probably ask around as well - I’ll bet there are a lot of abandoned wired controllers as gamers have shifted to wireless. Your friends (or their kids) may have one laying around. Or check the GoodWill.