AMain bought HobbyTown last year, they are one in the same company now.
https://www.amainhobbies.com/hobbytown-acquisition/cp1378
Side note, the motor I listed above was not really what I recommend installing, just what I know is the most powerful motor that will fit.
If I was going to run...
Street and loamy dirt on the ballfield are realistic but grass will be hard on the drivetrain and difficult to get proper clearance.
For what you want, I recommend a Mini Truggy at the least and possibly a Monster Truck.
You need to get a 540 size motor in there for a wheeler and for extra...