VanishingPoint has a freebie sci-fi looking autopsy table, no restraints, but it's a start.
http://www.vanishingpoint.biz/freestuff.asp?StartNo=252
 
Also, the MedBay is on sale at DAZ at the moment, but again no restraints.
http://www.daz3d.com/i.x/shop/itemdetails/-/?item=2199 
 

Forget all of my above suggestions, Davo's Madlab 4 is on sale at DAZ too! Wicked exam chair type thing with restraints.
http://www.daz3d.com/i.x/shop/itemdetails/-/?item=5199&cat=&_m=d