Just curious, about the Blue Ox Auto Stop you had before: When the cable broke, did you look into just replacing the cable with parts you can get at most hardware stores, Lowe's, Home Depot, etc? Thats what I would have done, I know a few people have done that with a Readybrake cable. 'Tis one of the cool things about a simple, mechanical, cable-operated brake system. Nearly anything that could break, you can replace easily and cheaply with parts you can but at many hardware stores. Not sure if that was the case with Blue Ox's Auto stop or not, though?
Anyway, as to your specific question: Have no idea if the tubing/sleeve is same size as Readybrake's cable, and could be used with Readybrake. I'd definitely check it and see once you get the Readybrake. If it is, you may not need a professional to do the installation. You could just slide the Readybrake cable into the sleeve, attach it to the brake pedal and you're good.
Did your old Auto stop include a break-away system of any kind, like Readybrake's Readystop product? If not, I would seriously consider getting a ReadyStop also, and installing that on your toad.
You're definitely making a VERY good decision, getting away from the electronic box type brake systems, and going to a Readybrake. It (Readybrake) is truly the only system I'll ever own. Soooo simple, no electronics to muck up, no drain on battery, no way for it to over-brake and damage your toad, AND costs considerably less than any other system. You just can't beat it. I just got done installing the Readybrake cable on our 2nd toad we just got, a Ford Fusion. Haven't tested it out yet, but will soon. Been using Readybrake on our other vehicle for 'bout a year now, it works great.
Will and Cheryl
2021 Newmar Baystar 3014 on F53 (7.3 V8) Chassis ("Brook")
2018 Jeep Wrangler JK ("Wilbur")