It doesn't matter if you decide to buy the parts separately or as an all-in-one. The price is going to be about the same.
Esbuy has Pioneer DVR-106 with a black bezel and Firewire/USB 2.0 enclosure for
$189 USD (minus
$10 if you decide to go with the beige bezel).
You can buy the bare DVR-106 drive from
LiveWarehouse for $118 or $123 (black bezel is $5 more) and a nice looking firewire enclosure from PCMircoStore for
$55. They have other enclosures for a low as $46.