Hi
I don't think this was ever standard for a Major, i've had a couple of original ones and none had it . It's more likely you need an exhaust from a 5000 Y series or other tractor from the later thousand series after the short silver oval and before the tall black oval ones . I googled 5000 and got pictures, some had the cup, some didn't Maybe some cheap repro's don't have it. I did also find adapters with them, Maybe you could cut and weld the pipe to your original exhaust

.
I just picked up a used exhaust from a tractor wreckers here in canada from a power major, somebody had fitted one of those exhausts to it like you want. It is now on my County as the pipes are the same size, and it looks better than the creation that was fitted, it's still not the correct type for a 954, it should be the short silver oval type but it works

.
I just read the small print at the top of the picture thats a later 0000 series part number shown , cross referencing that in a google search should find the exaust you want hopefully.
Regards Robert
A Fordson is for life not just for Christmas !.