And to go with that 1955 edition above, here is a 1st /1st from 1925 I just saw on eBay:

eBay Item #253471686239

Here's another copy, less desirable but very reasonably priced, from the same seller:

eBay Item #132532070677

Not sure how rare these are or what a good asking price is...

Seems like a decent price for an Uncorrected Proof of The Silmarillion (Houghton Mifflin): eBay Item #162996045243

Note: Price was originally $75 Buy-It-Now; that changed quickly.

Interesting - there's at least one typo visible - "The History of the Silmaris" in the third picture (attached here). I wonder what else was caught in the proof stage, as this did not make it into the first edition. The page ordering visible is different from the first US edition, as well.

Not sure if this goes here or in "Wonders" - ex library copy of Thesaurus

eBay Item #162787450035

HM, I've got one of those, together with the promotional leaflet:

... and companion booklet:

... and letter from the author:

What do you think, $1000 for the lot on eBay? ;)