You need to work out what you need...
You MAY be lucky and only need a link arm to connect the front of the engine to the end of the "piston" on the steering cable.
If your engine is like I think it is then there is a sort of U-shaped part comes forward horizontally at the front. Does it have a hole (approx 10-12 mm diam) right in the middle?
(2) Throttle and gear.
At the console end you can use "any" (e.g. mariner, yamaha) throttle. They all use standard "morse" cables. You will need to get the right end adaptor for both the control box and the engine.
I expect at the engine end the tiller throttle and gear links use very short morse cable to the same system, but you may need some sort of guide bracket / assembly, or grommets for feeding them through the casing etc.
(3) Electrics - kill cord if nothing else.
Even if you don't want electrics you need a kill cord at the helm. The tohatsu control could be marginally easier as you will be able to get a loom - but for two connections you can easily do your own wiring. You'll need to work out where it goes at the business end.