The Collaborative International Dictionary of English v.0.48:

Receiptor \Re*ceipt"or\ (r[-e]*s[=e]t"[~e]r), n.
   One who receipts; specifically (Law), one who receipts for
   property which has been taken by the sheriff.
   [1913 Webster]

Bouvier's Law Dictionary, Revised 6th Ed (1856):

RECEIPTOR. In Massachusetts this name is given to the person who, on a
trustee process being issued and goods attached, becomes surety to the
sheriff to have them forthcoming on demand, or in time to respond the
judgment, when the execution shall be issued. Upon which the goods are
bailed to him. Story, Bailm. Sec. 124, and see Attachment; Remedies.