I don't know how to do it in Premier per say, but you can do this eazy peazy by importing the clip into AE, making the magic hand in hand with one of the tutorials like the 'teleporter' - tweak it a bit, at a site like 'videocopilot' [google] then throwing that back into PPro. Don't have PPro you say, download a 30 day trial get it donr, move it back into PPro and move on.
You can do your chromakey in Premiere and export as a Flash with alfa.
Then you can add it to your websitepage.
Yes, the simple Keying in PrPro should work fine and the Flash with Alpha will separate it out. AE has the potential to do a better Key, but if you shoot the model without really poofy hair, or similar, it should be a piece of cake.