Shaggy

What a great and informative post! Just as a supplementary footnote; the neck on the OP's bass was almost certainly made by Steve Smith. He was an incredibly talented luthier who founded Heart / Heartwood guitars, and later worked for Goodfellow in the '80's, where his speciality was neck construction. After he left Goodfellow he took a stack of the necks he'd made with him, and set up a guitar repair /custom build workshop in Southend-on-sea, soon building a solid reputation amongst guitarists and bassists for the fantastic quality of his work. Some of the stashed Goodfellow-spec necks evidently found their way onto his occasional custom builds, including my treasured long scale semi "EB-2" (pictured) which has become my go-to bass for most projects. Sadly, Steve recently passed away (2017?) Really lovely bass in the OP, and a good price - bump and GLWTS

Chopper Blue? As I recall they were almost always red or yellow....... Lovely bass; looking for an old SR4 but this so nice

I think at the start of Kramer production Koa was used for the bodies (as with Travis Beans), but they soon switched to using maple and American black walnut (the 450B being walnut; also it didn't have block shaped markers). I have a 650B and 450B and don't find them unduly heavy. Lovely example in the OP and a good price, GLWTS!