When the .204 first came out ('04) Remington-Peters produced some factory 39gr SBK ammo that shot excellent, actually quite a bit better than the Hornady 40gr..I haven't bought any factory .204 since '06, so I'm not really sure if it's still around...
I just Googled it and while Midway lists it, it's now listed with a 40gr bullet and it not available,,,Kind of on the 'rare' list...