$1200 for the steering cables is 3X what this should cost! I had the M/C dealer replace the cable on the 2001 205V (same layout as your boat) and the entire cost (including cable) was $400 and that was in Calif bay area where labor rates are pretty high!
I've had the boat apart and the cable is pretty easy to see and get to. This is probably a 2hr job for someone that has done this before. If the dealer isn't a M/C dealer, they probably don't know how easy this is so trying to make sure they don't eat it on the job- so I would take it to a M/C dealer. If they are an M/C dealer, I'd shop around and find another dealer that isn't trying to have you pay for their kids orthodonics bill singlehandedly