Lets keep it easy for ya.....
Well, if that is what you "want" to beleive, then buy from CMMG here on the site. They are selling lowers that are listed as pistol lowers from the manufactuer. I was also told that the MEGA lower is now available as a pistol lower from the factory (different seller, www.carricozarmory.com/) sells the MEGA.
Also, Vulcan Arms sells their carbon/armide lower as a pistol.
So there are three manufactures that now "list" their lowers as pistols...... problem sloved for ya. And two dealers that sell those lowers. Just buy it from them online, and have your transfer dealer send their FFL and you're set to finish the transaction. I HIGHLY SUGGEST that you tell the dealer prior to them transfering it if they will transfer a *stripped AR pistol lower*. As you stated, some might have an issue w/ it. You might have to ask around before someone will do it w/out any reseravtions.
I won't bore you w/ the details..... even IF you had the correct info, some FFL dealers WILL NOT BELEIVE YOU. (Okay, sum it up, any stripped *virgin* receiver - ie, never had a stock attatched to it prior to being built to a pistol. Got that right from a manufactuer.)
Oh, forgot to mention, if you state has any special procedures for pistols, don't forget that stetp too! Example, handgun registration, or a permit to buy a handgun, etc....