I wouldnt buy anything new from Holley. Personally Id contact someone like Drew at AirFuelSpark. He specializes in restoring & rebuilding only vintage Ford Holley carbs. If he cant sort you out with a concours original he can build /recommend you something that will run way better and be as close to authentic as possible rather than any off the shelf offering from Holley. Just a warning - he does have an obsession for FE engines and 4x2 setups.
https://www.afscarbs.com/
The problem is?. For a 67 or 68 390 carb, I wouldn?t suggest using a 67-68 carb if the engine is modified.
These particular carbs (67-69 GT 390) are pretty darn specific to the engine.
From his description, I?d suggest an old school 3310 or a 650 double pumper.
I love putting the original parts on original engines, but this is the one exception where it generally goes badly.
To the original poster, I?m sorry I don?t have a suggestion about a new carb, I simply don?t deal with them enough to make an educated guess there.
Dp