If the price really 'iz' right and you really want it, buy it, then get a hack saw!
Or, take the rails to a machine shop/metal fabricator to cut the rails to the desired/workable length.
Have no idea what the table extension is made of, but my SWAG (Scientific Wild Arsed Guess) is it could also be cut down or a new insert made to fit.
Now as for your "sticker shock" over the shipping charges/total cost, check out what a good replacement aftermarket fence system costs these days including shipping. Saw Stop's fare just might seem to be so exorbitant after all. Nothing seems economical any more. If you ordered from Saw Stop, shipping rates to you would be cross country. Same with a Saw Stop dealer, the parts comes from Oregon.
As for the blade stop cartridge, yes that needs to be replaced after firing. But depending upon the blade, teeth can be replaced. There was a post on Saw Mill Creek a while back 'bout a Saw Stop user who sent his blade back to Forrest for repair. He claimed it came back good as new. Probably a great deal depends upon the quality of the blade.
I am not a fan of some of Saw Stop's advertising or marketing approaches. Not to incite/arouse ill feelings or start an argument, but let's say you trip the cartridge and a new cartridge and new blade is US$200.00. Depending on the type of an injury, $200.00 is -- or could be -- small compared to being treated by a physician or at the ER/hospital and may include time off from work.
Last edited by Ray Newman; 03-24-2016 at 12:18 AM.