Searching for the right bit

I went to the local feed store and stopped by the great wall of bits.  I was looking for a 5 1/4" bit.  So I look at a few bits and found that all three I looked at were 5" bits, so I start looking at more bits on the great wall and each one that I looked at was a 5".  I think I looked at every single bit on this great wall,  snaffles, french links, twisted wire, pelham and curb bits, and all are 5" in width.  This great wall of bits consisted of ALL 5" bits. Mind you this feed store is smack dab in the middle of quarter horse country.   If my friend needed a bit for the many warm bloods she has which range in many sizes she wouldn't find the size bit she needed.  And with that said I am now on the search for a bit that my horse feels comfortable in.

My preferences...

German Silver
French link
Egg butt snaffle
Copper

I recently purchased a french link snaffle, which was classified as a level two, but my horse just wouldn't have it.  I set it in his mouth several times (over two dozen) and he is getting to the point of not allowing it in his mouth.  I've driven him in it just as many times and rode him in it, but he doesn't respond to it.   It's the right width, but it's a lot thinner than an Egg butt snaffle.  I can only assume the angle of the bit and the thinness is more than he needs and is causing some discomfort for him.   I originally was using an Egg butt snaffle in copper and he seemed to be ok with it, however he would bite the bit to avoid it and this I deduced was related to the width which is 5" and he measures out at 5 1/4, so my best bet would be a 5 1/2".

The french link snaffle I am using now is also causing my horse to toss his head as if he were shaking his head yes very fast, thus telling me it's not for him.

Kind of pricey, but putting in the order.