Updating using only SCM sales. Let's see how this goes.

https://steamcommunity.com/market/listings/440/Nice%20Winter%20Crate%202012%20Series%20%2353

This is being suggested on 18 August, so we're going back to 11 August at max. Sales are as follows:

1x 0.08 USD (Aug. 11)

2x 0.07 USD (Aug. 11 & 14)

1x 0.09 USD (Aug. 17)

Given we've got multiple points, we've gotta range it. Using SCM key value. Currently worth $2.38.

http://web.archive.org/web/20180818125521/https://steamcommunity.com/market/listings/440/Mann%20Co.%20Supply%20Crate%20Key

Low value: .07 - .07/2.38 = 0.0294117647 = 1 ref (https://gyazo.com/97e5d1a088ad7208447a7662488b75a5)

High value: .09 - .09/2.38 = 0.03781512605 = 1.22 ref (https://gyazo.com/e8688714c84d31a217d8797d4d72fae3)

For reference, I was unable to find any other listings.