Going through trade.tf I actually didn't find any sales for 1.33.

Sales / Offers / Adds

http://www.tf2outpost.com/trade/13383998 bp.tf price sold, unsure what that could be (but knowing outpost, it was probably 1.33 :c )

http://tf2tp.com/trade.php?trade=9698833 1.66 sold

http://www.tf2outpost.com/trade/13547745 1.66 sold

http://www.tf2outpost.com/trade/13523895 1.66 sold

http://www.tf2outpost.com/trade/13537467 sold for s. syringe (1.66)

http://www.tf2outpost.com/trade/13543074 2 ref sold

http://www.tf2outpost.com/trade/10650252 several adds for 2 ref

http://www.tf2outpost.com/trade/13458446 2.66 sold

Buyers

http://www.tf2outpost.com/trade/13558809 1.33, none (young)

http://www.tf2outpost.com/trade/13487538 1.33, none (young)

http://www.tf2outpost.com/trade/11821460 1.33, none

http://www.tf2outpost.com/trade/10151682 1.33 has one but looks like they got from their own MvM game cause the id is only from himself

http://www.tf2outpost.com/trade/13280478 1.33, claims to have bought 40+ but none in bp at the moment

http://www.tf2outpost.com/trade/9632563 1.33 claims to have bought 79, but none in bp at the moment

http://www.tf2outpost.com/trade/13352839 1.33-1.66 hat, unsuccessful

http://www.tf2outpost.com/trade/13135472 1.44, none

http://www.tf2outpost.com/trade/13556917 1.44, none

http://www.tf2outpost.com/trade/13250951 1.44, none

http://www.tf2outpost.com/trade/13562784 1.66, none

http://www.tf2outpost.com/trade/13154778 1.66, none (one in bp has parts)

http://www.tf2outpost.com/trade/13388794 1.66 but bought from http://www.tf2outpost.com/trade/10650252 (outpost history)

http://www.tf2outpost.com/trade/13060344 1.77, none

http://www.tf2outpost.com/trade/13360195 2 ref, currently not buying

Extra / counterproof is always welcome.