You may not want to hear this but this is what you need to understand. I am not trying to be rude here.
You have now discovered that your gun does not fit and you need to find one that does. However, your requirements are not in fact very specific that are very very vague. Your description is not a fitting specification. A small change at the stock makes a big difference downrange.
Now that means 2 things.
1. A properly fitted stock is very personal.
2. Any variance in the mount (either gun up or gun down) can/will negate the benefit of the fitting as the rear sight (the eye) keeps changing.
Despite what the 'smiths would like to tell you it is very difficult to actually create a perfect fit for a variety of reasons which I will not go into here but is mainly to do with the act of fitting not really being representative of taking a shot. There is always an element of getting used to a stock. There are many elite shooters who I could name who have had their stock fitted by their sponsoring manufacturer who end up taking a file to it when they finally get the gun

. So it is not an exact science.
What you don't want to hear is that to minimise the pain, you should definitely buy a stock with an adjustable comb in the first instance. Get a coach to set it up with you on targets. Your mount is likely to improve with a better fitting gun and you will begin to get a feel for further adjustments that you need as your shooting improves. Having said that don't keep fiddling with it. Get it about right then learn to live with it. If you are always a bit high for a few months then that may be a reason to tweak, but not on the basis of a couple of outings.
Fit it on a real target, a teal at the top for example. Not on a pattern plate. 'Smiths want to use a plate, Elite shooters think they are the devil incarnate.
Do not get a stock bent, it will move back.
There is a reason that most new shotguns are designed and marketed with an adjustable stock.
I would also suggest that fit is not actually the most important characteristic of a gun. You can change the fit. However you need to get a gun with dynamics that suit you. If you are 6'7 and built like a tank a short, light, fast gun is going to be completely overpowered, equally if you are 5'2" a 32" gun that swings like a concrete fence post (not all do) is not for you. Get this wrong and you are stuffed (barrel weights are a waste of time, they are fitted at the wrong end)
Good luck!