WTB: road race Holley carb for 500-550hp V-8

OK gang, I'm putting the finishing touches on my CorvetteKart engine build and it's time to buy a carb for it. It is basically a similar set-up to an SCCA American Sedan small block Chevy spec. It's a stroked 383 build, 11-1 compression and should make in the neighborhood of  500-550 crankshaft HP at 7500rpm. 
 

I need a carb set-up for road-racing and was hoping someone had a spare built one sitting on a shelf somewhere. It's likely not something that I'll easily find used, but you don't know if you don't ask.

I might have what you need though I'm not too familiar with carbs.  It's a Holley 4 barrel that came off a 450HP 6.3 liter/393" Ford Cleveland.  I'm going to use my fuel injection system.  I'll grab some pics and post them here soon.  

Alright here's what I've been able to decipher.  It's got a 4/13 (April 2013)date wheel on a casting and is labeled Holley Performance.  Manual choke, mechanical secondaries, dual fuel inlets-one per bowl.  
 

I don't see any other markings or labels on it so I can't tell you a cam rating.  Not sure what it is worth either.

Thanks, but I'm looking for a "prepped" carb. I have one, but it's built off of an 850cfm Holley and was running on an 850hp drag motor. It's too much for my current build, so will likely get sold for a smaller 650cfm build.

That's a 4779, which is a 750cfm "double pumper". Manual choke, mechanical secondaries, dual accelerator pumps, etc. That's a GREAT carb, just not what I'm after. 
 

Here’s a link to the description from the Holley site.

The main difference for a road race carb are the floats.  Use these floats and most Holley carbs can work for road racing.

Floats

I've got a Holley Demon 750 if that works for you.  I can get pictures this weekend.