I bought this a few weeks ago, and have been dealing with getting it from Japan to the U.S.

It seems as though 1978 is fairly early for a  Cocobolo Series I:

Looks a lot like the wood in 78-1100, currently being restored by [elwoodblue].

Pretty stuff.

I'm really looking forward to hearing it in person.

Noice. No shot of the headstock?

Just found some:

Again: noice!

I'm excited, but they changed the rules for importing musical instruments made from CITES woods earlier this year, and now there's a step that requires a customs broker.

Very nice! Really like the dark wood. Hope you can make some sound samples.
You say it's cocobolo, but the papers say the top is rosewood?
Where did you buy it in Japan?

It was at Guitar Traders.

I showed it to Mica when I first saw it, and she and Susan both said Cocobolo, which was my first impression.

Beautiful bass!  I believe cocobolo is a type of rosewood.

Dalbergia retusa.

Beautiful looking bass, personally fond of basses with dark wood tops.

78-1172 has a Rosewood top and back, the wood and color looks very similar and it would have been built around the same time. 
https://club.alembicguitars.com/series-i-basses-and-guitars/78-1172-brazilian-rosewood-5-string/

Mica could not confirm the origin of the Rosewood used for 78-1172 with only a visual inspection but another luthier/wood collector told me it was Brazilian Rosewood. That would be a harder wood to ship internationally since it is now banned. Rosewood and Cocobolo are both oily dense woods and would have a similar sound. I would not be surprised if you find a lot of finish-checking on 78-1186 when you get to see it in person. 78-1172 has quite a bit, it is very common on instruments made during this era using the same type of finish.

Hope you can get your bass through customs quickly and start to play it!

I've admired that bass for a while — I love the fan headstock!