Noun for "receive"?

Receipt works. As in, "receipt of the items has been acknowledged."

Receipt \Re*ceipt"\ (r[-e]*s[=e]t"), n. [OE. receite, OF. recete, recepte, F. recette, fr. L. recipere, receptum, to receive. See {Receive}.] 1. The act of receiving; reception. "At the receipt of your letter." --Shak. [1913 Webster]

Likely variations for your case would include

"Ten deliveries were made but there are only five received items on record."

"Ten deliveries were made but the records show only five items were received."

I think you said it already: "deliveries".

The word you are looking for is Received

as in

Ten deliveries were made but according to our records only five were received