The first Holley I bought was "New" thru Ebay $150. What a piece of crap. The second Holley I bought was new from a local parts store at about $300. Another piece of crap but better than the first. Bought a new Edelbrock 500 for $200 , bolted it on the car, set the idle and drove off into the sunset. The carburetor for people who hate to mess with carburetors.
The car is just as fast and maybe even faster. Starts better hot or cold, cold idle is better, everything is better. If you need a Holley 1850, I have a couple I will sell. Neither one has many hours on it because I spent more time messing with them than driving the car. The only down-side is that it appears to be a little taller and there are some air cleaner clearance issues but they are much easier to deal with than taking those darn float bowls off, etc., etc.