Here's the Carolina Mantis.
>>3320257I don't know nikon lenses well enough to point at one. The canon 100 macro (non L) is pretty stellar. They also are going for ~350$ right now in the used market. The twin light for nikon would probably be good for what you do. I haven't bothered with the canon one because I need more control and it just wouldn't be powerful enough. You could try renting one to see if it would be enough.
The bellows is miserable because of how unwieldy the whole thing is.