Morgan Fry charges £75 for a reface on an ebonite mouthpiece -
http://morganfrymouthpieces.com/content/mouthpiece-refacing
"Standard refacing includes optimization of all of the most functional parts of the mouthpiece, typically including (but not limited to) the following:
Flattening the table
Correcting the facing curve
Thinning the side rails
Correcting the baffle
Correcting the throat
Opening or Closing the tip opening (up to about .010")"
seems like a bargain to me...
the advantage of getting your mouthpiece worked on by someone like Mr Fry is that he'll try his best to do what suits your requirements. An off the shelf mouthpiece may fail in that regard.
Getting what you want without spending months/years searching for 'the one' seems like a sensible idea.
There are so many improved Link type mouthpieces out there you'd spend forever trying them all and most of them are made in the USA so have limited distribution over here.
I'm sure Ted Klum, Phil Barone, Raphael Navarro, PhilTone, Aaron Drake, Eric Falcon, Fred Lamberson, Ishimori, Aizen etc etc all make wonderful mouthpieces, but how would you ever get to compare them side by side and find out which is the best?
If you've got a mouthpiece that's 'nearly there' and you can get an expert to adjust for you, it's worth a try
One of my friends got a cheap secondhand metal Link and sent it to Morgan to be 'Floridated' and was delighted with the results - and it was cheaper than buying a brand new Link STM
Custom mouthpiece modification is the one thing I've not tried yet, but it's only a matter of time...