Hey Matt. Welcome to the forum.
Sadly, I have no info whatsoever to help you. The ELF seems like a neat little homebrew kit. I have very little in my collection from that era of microcomputers -- most of my knowledge and experience starts with prefab PCs like the Apple II and TRS-80.
With a little persistence and cunning, you can probably track down the people you listed. That's your best bet in terms of finding information. You just have to be willing to ask around and talk to strangers.
If you find those people, they may have old CHIP-8 / ELF documentation lying around that you can have (or have copies of). Also, keep an eye on eBay in case some of those magazines show up, although I do suspect they are pretty rare.
For greater exposure on the Internet, you can write an article about your quest for CHIP-8, VIP, and ELF info for VC&G, and I'll put it up. Once an article like that is live, it has a way of bringing people out of the woodwork that you never knew were there. VC&G has a pretty high Google profile, so it helps quite a bit. As it stays up, people find it and post comments on information that they know.
For example, someone might, in the future, look on Google to see if their VIPER magazine collection is worth anything. If there's an article that mentions VIPER magazine on VC&G, it will probably be one of the top search results -- that person will find the VC&G page and will be able to contact you.
Let me know what you think. And please keep us updated in your quest for info.