Benny that looks like a pretty darn good survivor, it might be worth more as it is rather than restored. I wouldn't mind a bike like that at all, rather than a pristine restored one.
It may be worth enough to get hold of a late model bike or one to fix up for the child, also if he wants to ride street and parks then that isn't really suited, get him rolling on a little 16 incher first I guess....(sending the DB to me would be much more suitable

I'd see what is around that era on Ebay and so on before you decide to do anything mate.
anyway the guys here know heaps and will help you no matter what you decide.
PS: I wish I'd been at the garage sale

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