I'd go for O'Neil for Lafai and sign Oats in place of MacDonald:
1. Dufty
2. Pereira or one of the 2 new boys
3. Lomax
4. O'Neil
5. Oates
With Lomax and Oats on the right, our defence will stand up to any team.
The biggest problem in the backline isn't Lafai, its Dufty and unless we get a genuine first grade quality fullback we will struggle.