I'm reading the rules for Unusual price suggestions, where it is said that "Sales older than 2 months old are not valid proof; this does not mean that they are not useful. Feel free to include them to provide supplemental proof. Just don't rely on them to set your range." and then "Exceptions: For very rare hats, if there have only been 1-2 sales in the last 3 months, a trade up to 3 months old is okay to use as proof to establish more data points. Keep in mind, new sales should take precedence over older ones."

I guess the Peace Sign OMF could count as a 'very rare' hat since there's only 3 of them, but I'm not entirely sure what is meant by saying "supplemental proof", "don't rely on them to set your range" or "new sales should take precedence over older ones."

It also doesn't help that the marketplace.tf graph is the only proof, there's no Paypal receipt of the transaction itself available.

I'm going to wait for a mod to comment first before possibly resuggesting