Interesting, SF... care to share which "loft"?
I can see buying a headsail or a spinnaker that way (on-line), but the fit on a mainsail is much more critical, and there I agree with Jarcher and others re: buying local. If you're not racing look for a small independant loft; they are often less expensive than the major players like Quantum, North and others.
Comparatively the prices of on-line providers are very tempting... but...
As for touch-up and restitching, you've little choice but to go for local. You'll probably get a better deal getting your repairs done by the same guy you buy the new sail from. Hopefully some of the other local members here will chime in with some suggestions!
1984 Fast/Nicholson 345 "FastForward"
".. there is much you could do at sea with common sense.. and very little you could do without it.."
Capt G E Ericson (from "The Cruel Sea" by Nicholas Monsarrat)