No. Its not the K-30 but another model specially made for the company 38th anniversary.
Sorry, never heard of K-38.
Are you in the US? Can you disclose who the dealer is?
I have no concrete reason to doubt your story, but the "K-38 special promotion for the 38th anniversary" story sounds very fishy to me.
Go to
https://www.kawaius.com/ and click on "Upright Pianos."
There are K-18, K-25, K-30, K-50, K-60, K-80.
There is no model K-38 that I am aware of.
Kawai celebrated its 75th anniversary in 2002, so the 38th anniversary story makes no sense to me either. (Which company's 38th anniversary? The dealers?)
If you are serious about buying this "K-38," this is what I recommend:
1. Go visit the dealer and look at the piano, copy down the serial number of that particular piano (not any other piano, must be that particular piano that you're interested in). The serial number is usually stamped on the tuning pin area (open up the top lid and look for it yourself).
2. Go to
https://www.kawaius.com/ , click on "Contact Us" and contact Kawai US (the distributor). Double check with them the "K-38" model and the serial number. If the "K-38" model is genuine and the serial number checks out, Kawai US will tell you. (I contacted Kawai US before to double check on a used Kawai piano I was thinking about buying, they were very responsive.)
Good luck!
(p.s. As for whether you should increase your budget and get a U1 -- that's entirely up to you. Go play the U1, go play the K-xx piano, and buy the one you like best within your budget -- there really isn't much more than that. Any of these pianos can easily last you 20~30 years as long as you take good care of it. Good luck!)