I would budjet at least $4,000.00. And if you plan to have a rigger do the whole job that won't be enough.
There are usually complications when converting from rod to wire. I would not consider doing a job like that without pulling the mast.
Mechanical fittings, regardless of who makes them, will take longer to assemble than it will take to run a swage through a machine. (Wire-Tecnik is the best IMO).
No one needs to remind me about swage cracks. When the swages start cracking, the wire should be replaced. Period.
I think you should rethink the whole rollerfurling issue. On a long passage, the less time you spend on a pitching foredeck man-handling a sail, the better. Just make sure it's installed correctly, the halyard is running through the restrainer and you use pennants on the various sails where needed.
Hayn Enterprises makes a great backstay insulator that is promoted as being failsafe. If installed correctly, is should be.
Find a rigger who will work with you, advise you and perhaps allow you to do some of the work yourself while the stick is down.
You will probably find that most riggers will not give you a quote. We only give estimates and urge the customer to be present as work is performed. It's a lot easier than trying to explain later why something took longer than anticipated.
Don't take shortcuts. Take this opportunity to replace the electrical wiring, lights etc. Get to know the system that makes your vessel a sailboat, the "rig"