What do you recommend for a solid state for office

Bel Canto S300i speaks for itself for half of what you want to spend for used unit. It will work with bookshelves like magic
Outstanding performance at any volume level, precise and detailed and very analogue sounding similar to class A amps or tubes, compact size, never runs hot and also an eye candy.

rogue sphinx

Second for the Rogue!

I tried a few pairs of active studio monitors and didn't find the sound quality to be that good. You should be able to get much better sound with separates that cost less.