[Rimrock]

We're not talking about high amp motors in such a model. Pump motor will draw the most, like in the neighbourhood of 10-20A max, track and slew motors like 5A, just to indicate some numbers. But anyway, ESC for this purpose are relative cheap, weather they are 10 or 50 Amps, so one will pick a ESC that is well above the motor rating, like 25-50A rated. One should not over-dimension the ESC too much either, like getting in to 100-150A, because they have a certain 'standby draw of current'. The brand is not so important at this Amp level, many cheap options at ebay and similar would do just fine is my experience, and one can have a couple in spare. When it comes to high performance RC cars and airplanes, on would rather go for more costly, branded ESC's.
Pump motor is usually brushless, for high efficiency, and slew and track motors standard brushed motors (slew and track should not be using brushless motors, as they not have the internal resistance against rotating at standby/'parking mode') E.g MFA Como drills, UK, delivers durable industrial type planetary gearmotors well suited for track and slew, at a relative reasonable cost. Cheap ebay gearmotors, 15-20 USD, would not be such a good option in a 1:10 machine.