Well, no- relatively speaking very few Italian replicas get anywhere near Turnbull.
Certainly not "most of the replicas".
I don't see any possible way Colt could turn out a gun that'd have any quality worth buying for LESS than an Italian SA.
Italy has a much lower wage level, Colt can't compete head to head in that area alone & sell for less.
The Cowboy, when it was in production, WAS the equivalent of what you're asking for, and it didn't sell well enough to stay in the line-up.
Even if it were brought back, which is highly improbable, and sent to Turnbull, I seriously doubt it'd make any money for Colt.
The Cowboy was not liked enough to keep it in production.
A resurrection, but with a fancier finish, would be unlikely to do much better.
Developing a new design with different guts would put Colt in the same position as the Python- expensive R&D and start-up inventory costs, with inadequate return on investment.
Cheapening the Peacemaker to get it down to $700 would cause massive outrage among purists (80%-90% of Colt's SA market), and result in a revolver with cast frame, cast gripframe, MIM internals, and an inferior finish (NO way Colt could pull that price off with a Turnbull treatment).
CAS is no longer the driving force that was largely behind the Cowboy's development, there are so many other areas that Colt would see a far greater return on (keeping up with demand on current models, even a new DA revolver if & when), that sinking resources into a new Second Tier single-action wouldn't be worth the money.
As for bringing back the .22s, same startup problems. The guns would have to be developed for CNC programs, parts vendors arranged, parts inventories worked out. To be truly competitive with Ruger, which the .22s weren't, they'd have to be a shade nicer in appearance, at least almost as durable, and sell for roughly the same price, or no more than 10% more.
That'd be extremely tough to pull off.
Building a .22 on a full-sized SA frame cuts down on manufacturing & inventory costs, since many parts already in the chain can be used, but the result is a heavy gun, and those don't sell well in volume to .22 shooters.
It's not a simple picture, and there are many factors that have to be considered.