Looks like the cheap price was for the signle guide rail and the $108 is for the entire kit. Notice they didn't update the list price. May want to find someplace else to buy, that place looks like they are not that bright.
Found a similar one
here for $107.61
Kit contains the following: timing chain, cam sprocket, crank sprocket, LH and RH chain guides, tensioner, tensioner gasket, front crank seal, and 2 timing cover o-rings. Timing cover gaskets are not used on this appplication; use the appropriate liquid gasket sealant instead.