I'd persevere with manually focusing your nifty. If you are playing with DoF, you will in many scenarios need to focus manually anyway. Especially if the D60 (like the D40) only has three focus points. Maybe you could try a view finder magnifier.
I tend to always try and take a shot to test image sharpness, preview it and zoom right in on the area I want focus to be sharp. If necessary I can take another shot.
Of course, this only works easily with non-moving subjects.
You could of course, sell your D60 and maybe put what you make, plus that extra £170 towards a good
second hand D80 or D90.