Help with the right brake line

I'm having a bit of trouble with the lookups for the right part.  I have a 1981 KZ1000J/A frame and have been having issues with my rear brake freezing up, so on advice from here I'm looking for a new brake hose.  The problem is that the lookups I've done on various sites keep pointing me to 21" or 22" hoses, but the line on my bike is only 16" to the very ends of the connections.  The parts diagrams I have call for a 43059-1180, but it seems that may be a discontinued part?  However I can't seem to match that part to a description that tells me the expected length.  I was hoping to get one of those with the braided sheath, and I would assume one of the generic lines should fit?

I guess what I would like to understand is how the actual measurement is taken (or what size I need for my bike, if anyone knows).  I'm not sure if I should measure to the ends of the connectors, or to their centerpoints?  And is there anything I should watch out for when ordering the replacement (Amazon seems to have a lot of options)?

If you are reasonably handy with tools you can make your own lines from Earl's parts.  I've got a photo tutorial inside my 750 build thread.  It's easy to make these lines and you never have to worry about getting length right since you can fully customize before cutting the tubing.

Another option is that Z1 enterprises sells modular lines in 1 inch length increments, along with threaded banjo fittings.  There are different styles and colors, but here is an example.

www.z1enterprises.com/gr83300.html

@Nessism - I had considered that but figured I'd rather just get something pre-made.  Sometimes it's easier to just not mess with it.

@DOHC - Yep I saw those, and noted the two different types of ends (Banjo connectors, that's the word I couldn't think of yesterday!).  I hadn't gone into the description though so I didn't see the explanation of measurements before.  And then the banjos are sold separately, which seems like it creates another point of failure?  I thought they would be a single crimped unit but I guess I haven't looked at my stock one that close.

So if I'm reading this all right, I need my center-to-center length (15"), minus 3" for both banjos, so I would order a 12" line?

Looks like I'll have some work to do in the Spring.  Try to get the brake cylinder cleaned out of whatever is plugging it so I can replace the hose, plus I have the parts on hand to rebuild the front forks but never got a chance to do that this Summer either.

Have you tried the banggood site? They have brakelines.

Have you tried Galfer ? I bought a set for my GPz front and I thought they were not quite right so they made me up a new set from my old ones at no additional charge. So, pretty good Customer Service...