For a street 383 in a fairly heavy car, been there & done that, and here's what I'm thinking given what Felix has told us so far:
You can either return the piston kit and get one with more compression from the same source, or look at 440source.com and see what they have. A cast piston will be fine but forged holds up better to detonation.
Not knowing the octane ratings in the Fatherland, I wouldn't want to go more than 9.0:1 on an iron-head Wedge @ 91-92 octane.
The Edelbrock cam is kinda short on lift, but IF you also need rocker arms, a 1.6 ratio would help that. Otherwise, look at more modern stuff like the various Comp Cams, Engle choices. Something in the 214-224 @ .050 and around .450-.480 lift will be mild enough for a stock converter at 9.0:1 CR. I've used as much as .504 lift at that duration with tall gears & stock converter and had very nice street manners.
With old stock heads & block, a surface cut is likely needed for flat decks on both. Good machine work, balancing, and a good valve job go a long way; find a GOOD machine shop that's familiar with American engines and has an eye for details. There's maybe .5 CR there without going nuts.
I like double springs on the valvetrain, and at least a windage tray. Use a dual-plane intake (look in the ads here for nice used), and a 650CFM carb would be adequate.
The Eddy & Stealth heads I've used all needed a better valve job, and the springs & parts were OK.