The publisher's edition statement for the Aeonian Press pirate is probably accurate. At least, I don't tend to question it. IMHO, it's not a rare book, or even scarce, etc. As to value, I have two variant bindings, and I paid about $20 and $15 for a mint condition copy of each, if memory serves, within the last few years.
As you no doubt know, the Williams/Epstein book went through an untold number of reprints (that I know of, at least 12 of the hardback version and 21 of the paperback version), probably in large part due to its popularity in the elementary schools.
I wasn't aware of the 80-copy-print-run edition you've mentioned. Do you have any info on the publisher, pagination, if it had a dustjacket, etc?