I called Suburban this morning, they were very helpful. This NT 30K is discontinued. This the NT 30 SP is the best replacement. It is a little bigger, but will fit. I ordered one so I'll see how it all fits together.
I am glad they were able to help. If you have any trouble fitting the new one up you might want to email Airstream. They had a service bulletin that explained my refit pretty good.
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