You can intercept the paste command and use it to paste and format e.g. as follows, but it will paste ALL images at the size you indicate.
See also http://www.gmayor.com/photo_gallery_template.html
Sub EditPaste()
Dim iShp As InlineShape
Dim oRng As Range
    Set oRng = Selection.Range
    oRng.Paste
    For Each iShp In oRng.InlineShapes
        With iShp
            If .Type = wdInlineShapePicture Or wdInlineShapeLinkedPicture Then
                .LockAspectRatio = msoTrue
                .Height = 141.64
            End If
        End With
    Next iShp
lbl_Exit:
    Set oRng = Nothing
    Exit Sub
End Sub