Yes it is parkerized.
and its a great GI 1911 for the money.
Easy question. With $400 budget, go buy a used Glock.
Don’t know why you seem to want .40 and larger. 9mm is fine for personal defense (with the proper load) and the ammo is cheaper. If this is your first handgun, I couldn’t suggest strongly enough that you go 9mm over .40 or .45.
You should be able to find a good condition used Glock 17 or 19 for $400.
But I really miss my 1911. I wouldn't mind having a Kimber, but I don't want to spend that much money. I'd rather use the difference to buy ammo.