I'm building a 383 for my 23' wellcraft I tend to take it easy on my stuff, I like to run without breaking if I can. I know lots of people with big fast boats so I'm tempted to keep up every now and then.

So you're certainly under 400hp......
If it's a budget issue and your not running too big of a cam or after the last 20hp at 5500rpm, go with the Weber off a Merc BBC (under $100). It will probably be jetted ok as is. The only thing you might have to fab/modify is an inverted flare fuel line. Although one from a Merc 260 SBC motor might work.
A Merc Qjet from a 330/365hp Merc would work for that too and are generally better at starting and idle.

I hope to be right at or just under 400hp. I'm running a fairly high compression ratio for a marine engine just over 10 to 1 and a cam that's going to want as much dry exhaust as I can give it.

Well Merc used the Webers on their 410hp 502s, so they'll flow in that range, and Qjets were used up to 370hp motors. Both are about 750cfm. So like I said, you might gain a few hp by going to a 800+ cfm Holley if you honestly think you'll be pushing 400hp, not sure if that would translate into even 1 mph more.
But since this is the "Budget" section, I'm going to guess that used marine Webers will be a lot cheaper and easier to find than marine Holleys.

What cam are you running and what heads are on there? I ran a RPM intake with a JET mod'd merc QJet and pull 436 Hp on the dyno. If you want to run a Qjet that is setup well for the 383 power curve in a boat let me know, I want to get rid of it. I have a pro systems carb on a single plane intake now, pulling just under 500hp.

The Weber Merc Carb 750 CFM is good to 550 hp. I believe he rates the 750 qjet good to 475 hp. The 750 Vac Secondary Holley is good from 400-550 and the 800 vac for 500+. This is out of Dennis Moores book "BB Marine Performance".

I'm going to be running a 750 weber on my 439 bbc. IMO a 750 on a 383 is going to be too big. 650 would be a good size for that motor.

I have a 750cfm holley on my 355,runs sweet!

here you be the judge

http://www.youtube.com/watch?v=I78vehnSmF8

nice !you are set up real good .i would copy your set up in a heart beat .how fast do you go???

in that vid lower 70's,,the boat throws you around a bit and its hard to read the gps at times..i dont have a recall on mine

mind you all the power is going through a volvo 280 drive..

Be real simple to email Holley for an answer.
http://www.holley.com/TechService/TechRequest.asp