Yes, they definitely have value and are also very collectible and tradable! Most of them don't seem to be really valuable, although some are. What is cool is the craftsmanship and art that went into the manufacturing of them. Most people collect them for those reasons. It's very much like collecting coins. I collect those more for the beauty of them then for the monetary value. If there is a lot of monetary value to them, that of course is okay, too! The more perfect it is, the better.
You might want to check out the ones that I found on the following site to see if you have some that are like the ones that you will find there.
american classic, Cars, Trucks-Diecast, Aircraft items on eBay.com
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