I have a Lamberson 7SB baritone piece that is my main piece...love 
the sound, but have never found a reed brand or clipper that matches 
the tip shape. The corners are too square and the tip rail is very 
thin, so I have always set the reed a little 'high' to keep the 
corners from causing squeaks, but have paid the price in response and 
articulation. If I wanted to fix this (I'm probably not confident 
enough yet to try it myself), what are the options. The tip rail is 
too thin (< 0.5mm) to just reshape, but the 'short baffle' is 
probably very important to the sound...should I just send it back to 
Fred with a reed to match?

By opening the very tip .001-.003", the tip rail should widen up 
enough to shape how you want.  It could be blended into the rest of 
the facing curve.  Probably not worth cutting the table to get back 
to the exact same tip opening, but that could be done too.  A little 
bit pocketknife and sandpaper work get the short baffle back to where 
it was.

You could practice some on a junk piece first.  I'll fix it for you 
no charge if you think its not right.  Or you could just send it to 
me for a no charge fix.  Or send it to Fred.