if you *really really* have to, get an aquapac. i dont think any of the major underwater casing manufacturers make anything for the fuji 2800.
and by the way, a "cheap" underwater casing will cost easily 200 to 300 dollars. but that's MUCH cheaper than buying a new camera because of flooding. an aquapac is supposed safe max to 10 meters, but i wouldn't bet on it.
digideep has a pretty extensive camera/casing listing, but according to
http://www.digideep.com/product.php?pType=camera&mID=12 , your camera is not listed. but i am not familiar with whether if indeed, a u/w case if available. try calling fujifilm singapore for assistance.
what are you trying to take underwater? if you're diving, you have to have a hardcase - an aquapac is definitely not safe, since it's rated for close-to-surface water depths...
seems like the aquapac is your only choice right now, as i have found out. the finepix 2800 is listed explicitly at
http://www.digideep.com/imgdb/aquapac.pdf
according to the company,
"Special Note:
Be extremely careful if you plan to shoot underwater.
Although with the clip sealed it is completely waterproof, the quick-action lever system means you could inadvertently knock a lever open underwater.
It was conceived for surface use and to protect against accidental immersion"