Ladies foulies for the shorter, bigger woman?

Following this one: my wife is looking for a new set of waterproof salopettes and she is similarly proportioned.

We found her last set as the largest Musto set available at the time. I’m surprised that they don’t make them a couple of sizes larger too or is the marine clothing industry trying to deny those that aren’t stick thin of a perfectly good pastime?
 
I was wondering if anyone know where I can get saloppettes in size 16/18 and for a short lady (about 5 foot)?
The same problem as with shorter bigger men!
I have to buy XXL and shorten the legs.
Tip - I cut a section out of the legs about half way up my shin.
Then I don't have to do any tarting around with the leg bottoms (zips, velcro, etc).
 
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