Fostex T50RP ............ $74 shipped
Google search "T50RP B&H"
This will link you to a page where the T50RP costs only $74. You cannot get this price searching within B&H's site (you'll get a page saying it's $129 instead). There are other shops selling it at $74, but they are a bit shadey looking with very few customer reviews.
I think this is a great price considering its popularity (and value) among DIYers has been climbing steadily over the last few months. B&H also has Shure SRH840 replacement pads for $14 (+$5 shipping?) if you want to start on your modding journey right away!
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This would have been posted sooner, but I wanted to receive the "your items have shipped" e-mail notification first