A suggestion: you may find the will on microfilm at a (LDS) family history center.
The profile seems to reference: Virginia, Wills and Probate Records, 1652-1983. ancestry.com. Brunswick General Index to Wills, Inventories, Or Sales, 1732-1948. ancestry.com, img 112.
From that image (which appears to be an index):
p. 288. Columns: Name; Will/inventory/or account sales; Year; Vol; Folio.
Tarpley, James; Will; 1781; Order Book 2; 167; [blank]
familysearch.org catalog search for location: "United States, Virginia, Brunswick". Among the results:
Court order books, 1732-1904
Virginia. County Court (Brunswick County) (Main Author)
Brunswick County (Virginia). Clerk of the County Court (Added Author)
Manuscript/Manuscript on Film
Salt Lake City, Utah : Filmed by the Genealogical Society of Utah, 1949
Richmond, Virginia : Filmed by the Virginia State Library, 1974, 1980
on 23 microfilm reels ; 35 mm
That comprises a list of 23 films. No entry seems to correlate with his (1781) will "Order Book 2," as, in that list, is: Order books, v. 2 1741-1742, not the correct date range. However, there is a film "Order books, v. 12-13 1772-1783" film no. 30666.
In any case, you may want to consider doing a search at a family history center, and order a couple films.
Alternately, (I don't know your location) you may want to make contact with the Virginia State Library and see if they have original books, films, etc.