Synthesize acyl chloride from aldehyde
There are many ways to affect the transformation, as you have realised, and many of which Loong has detailed below in his post. 

This answer gives one method which I would be confident of working practically, in the lab, using common reagents. A full search of Reaxys of SciFinder would reveal conditions/methods more suitable for a specific aldehyde. 

A Pinnick oxidation will convert an aldehyde into its corresponding carboxylic acid, which may then be treated with a reagent such as oxalyl chloride to give the desired acyl chloride.