Fact is a lot of good mouthpiece...very good mouthpieces can be made from old no name blanks.
The other fact is that it can take a lot of work and that work takes a high level of skill. If you cant do it yourself you will end up spending some significant money and if its not what you want you will never recover it.
...thats why a lot of these old pieces sit in drawers.
I sold a lot of old rebuilt pieces on ebay last year before leaving the country. There were some very good pieces for well under 200 bucks....but most players dont want to gamble. Also a player selling a piece rebuilt for me would have gotten less money than If I sold it....so, yes its very possible...but Im not sure its the ideal path for someone who is not skilled in mouthpiece work (for one thing...butt/bias cuts, take practice...more time, and more skill. Its easy to end up with a door stop.
...anyway..cool blog (I bookmarked it) and its always fun to read Marks Writing.
I keep looking for the FlemTone Ads...I think he should include at least one!