All we know about these premises is a single newspaper report:

To be lett, against Michaelmas next, a House called the White House and a very good large Malting-Office, situate by the Water-side at Nacton, near Ipswich, late in the occupation of Mr Thomas Beart, Hoyman, deceased; very convenient for Shipping of all Sorts of Corn, from a Key, lately made there. Enquire at the Three Cups in Ipswich any Saturday or of Mr Sparram, at the Sign of the Griffin in Framlingham (12th April 1740 edition refers to a John Sparham, Vintner of Framlingham).Ipswich Journal, August 18th 1739***

This was probably not a pub, but a malting office and quay-side used for the shipping of grain.

Based on the description of its location, it seems this may be what's now shown on maps as Yachtsman's Cottage. Unfortunately there appears to be no public access to that location so we may never be able to get a photograph.