My quantities are coming straight out of the manufacturers records.

The seller who has a quantity (no idea how many) has had them on ebay on and off for almost a year - averaging $35 a chip for the $1, $5 & $25. The $100 is worth a bit more, I agree.

The book you are quoting from was published a decade ago, so aside from the fact it was published before a large quantity of these chips was discovered, we've had the effects of a recession on those prices.
The current Chip Rack, which you mentioned in your first post, lists these at $50 each.
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