It's counter-intuitive, but the larger vintage Airstreams have generally the lowest value. If you want an idea of the minimum price, start with $3,000 for a "campable" Sovereign
(old appliances, no zip dee, tarnished, old axles, but all systems working). With all your new items, I'd move the target up to $8,000.
The mid-bath models are more attractive than the rear bath for two reasons. They are more livable and their weight distribution is better for the frame, so less chance of rear end separation. If your axles are new, you can add another $1,000. If not and you have knowledgeable buyer, worn out axles can really detract from the price, regardless of other goodies. Most buyers, however, are not knowledgeable.
When you say the interior is in "great" condition, that will not add much to the price, but
if it also has snap and eye appeal (no odors, great color--not the original orange--warm wood tone, nice flooring) then the sky is the limit. You can easily go above $12,000.