M&A offers the EMCO 1:7, but I will primarily be shooting 55 grain ammo.

Anybody else know of a source for a 1:9 upper with GI contours?  I hate the full length H-Bar on a 20".

Have you checked with Bushmaster yet?

Alternatively, having the barrel of your choice turned down under the handguards should be considered as an option.  I had several Colt HBARs turned down to 0.700 under the guards, although a true .gov profile would be slightly smaller.  In fact, except for the nastalgia(was used when I shot service rifle matches), my personal Bushmaster 1/9 HBAR could use the same "diet" plan!  It shot very well with 55 grain loads, BTW.

Paladin

+1 Bushmaster

http://www.bushmaster.com/shopping/barrel-assemblies/abbl-20a2.asp
check it out