By coincidence a few days ago, a red pad 357 mag No.1 came into the local gun store. It was priced a little under a k-buck, had a vintage scope on it; nice wood; pretty clean rifle.
I passed on it thinking too high for a donor, and did not like the balance which is purely subjective. I think it needs more barrel weight/length.
A custom build gives a lot of options, probably at less money than an original.
I suspect my build will be a No.1B type in 357 mag.