If you want to stick with Nikon glass, you might research what lens fits your needs first. Most of the upper-tier Micro Nikkor fast-glass is not cheap. Some will set you back several times the cost of a decent body.
There are "suitable" offerings that will work with Nikon mounts of course (Simga, Tamron, etc.), but IMO, Nikkor glass is like Porsche...there is no substitute.
