These are socket cap allen screws:
and these are button cap allen screws:
Go to
http://www.mcmaster.com/ and search through their listings, I know they carry them. I bought some 1.5" but they turned out to be too long, so get 1.25". The radiator came with self tapping sheet metal screws, but that wasn't going to work for me, so using a tap I cut 6-32 threads in the radiator mounting holes. The rubber washers were bought from performance pc's, but I think you could get them from McMasters for a lot less.
Here's some at McMasters: (these are Torx head though)
http://www.mcmaster.com/param/asp/PS...MainWidth=1073