Without seeing the piece in my hands I cannot say for sure what I would recommend, but I would certainly continue to consider a repair to the breech. Does the cable still has a lot of shoulder left on the caliper to secure the housing when force is exerted by deploying the parking brake? That is the only real force exerted at that juncture - the cable sheath is stabilized so the cable itself can move internally in the sheath. So, unless the majority of the cable shouldering is lost, then retaining the cable against falling out is not doing more than overcoming gravity and any momentum caused by the vertical travel of the suspension.
I also am not much swayed by the dealer's opinions in general. Dimmit/Dew has an absolutely awful reputation in my own experience with them and with the experience of friends who have relied on their service department , at least for Esprits. I don't know Lotus of Orlando at all but bear in mind that the dealership is primarily concerned with CYA principle when it comes to unconventional repairs. I would expect they would say "replace" - that way they have made a safe recommendation. There's nothing wrong with replacing things (including rotors) but of course it costs a lot of money. Did you get a quote from them on replacing the caliper? Is it available?
If you are looking for used I would suggest Sportscar World - both for the caliper and the rotors.
If you are trying to save some dollars here, then I would try some repair on the caliper. It is only the parking brake, so if the reapir fails it is not catastrophic. As far as the rotors, find out what minimum thickness is specified for the rotor. Measure the thickness of the rotor at several different spots, and make a decision about whether or not they can be turned without pushing them into a dangerously thin condition. That is more important than the parking park, since a broken rotor could be a very dangerous occurrence.
