Gene
Before you write them off talk to Allied Titanium
http://www.alliedtitanium.com/
They are working on a 25%-50% premium over SS. The major cost of a chain-plates is the labor for polishing. If you DIY and price your time at 10c an hour there is no competition. I was lucky enough to find a guy in Miami to polish them for $30, he is no longer around and I am looking at $50 +/- a plate. That would bring my total cost to $100 +/- a plate, not counting hours of fun driving around Miami and trying to speak Spanish. Casey recommends that chain-plates be pulled and inspected at 20 years. That will either be you or the next owner. I think you could recover the extra cost of Titanium in the sale price. If you are unlucky you may get crevice corrosion earlier.
Blow boaters are generally poor or cheap. I am both. However, I seldom skimp on critical items such as; chain-plates, fuel polishing systems and ground tackle.
Regards
Gerry