The #90 is not a shoulder plane
Derek Cohen (in Perth, Australia)
>.... it is a bulnose plane. The absence of a nose on this plane will make it difficult to trim tenon shoulders.
If you want a 1" wide Stanley shoulder plane then look at the #93.
Be aware that new Stanley shoulder planes (#92 and #93) have had bad press for their machining. They require a little tuning to bring them up to scratch. On the other hand, vintage models work very well. I have vintage #90 and #93 versions and am very happy with them. You would have to find one of these on eBay.
At the lower end of the price spectrum, the best shoulder plane is the HNT Gordon. Many here will agree that their performance rivals the best, regardless of cost. However, they come without the bell-and-whistles, requiring a hammer to set the blade (really easy to do). I have the 3/4" brass and ironwood version. There is a size larger (1 1/4" I believe), which would be closest to what you seek.
Regards from Perth
Derek