Saddle tree question

[Jennifer Thompson <jlthompson@earthlink.net>]

Hi all,

Am posting for a friend who just bought a new arab gelding.  This 
gelding has a very wide, flat back, with low withers.  I guess he would 
be what is called "mutton withered."  He is a very solid, husky type, 
with his barrel being shaped much like, well, a barrel!  To ride him, 
you feel like you'll be split in two.  LOL  He is not tucked up at all 
underneath, but is not fat.  He is just solidly round from front to 
back, with his back being very flat and wide and low-withered.

He has big white marks on either side of his withers from previous 
owners not using a saddle that fits.  My friend currently only has a 
semi-quarter tree saddle that obviously does not fit either, and is 
leaving dry spots right where the white marks are.

She needs to go saddle shopping.  To start, should she look for 
full-quarter bars, or "Arab" bars on a saddle?  What is the difference? 
 Which one is wider with a flatter pitch and wider gullet?   We just 
need a starting point, and with so many saddles advertised, need to 
start narrowing down the search.  She also wants to find a very 
lightweight saddle, not terribly expensive, maybe sythetic, or 
leather/synthetic combo.

Thanks,
Jennifer