Personally I'm a fan when you get to £400+ of buying small bookshelfs and an AMP (if possible a DAC/AMP combo), then later on you can add a sub if you want that next level/dimension of bass.
I went down my local hifi shops and demo'd a few setups, they where very good at recommending good pairings of amp/speakers. My requirements where to fit on the desk, so that limited me to the small or very small bookshelfs, but honestly they sound great with everything
However, for a small but good sounding setup, it would be a bit more like £450 to £500 for the following options
Speakers
DALI Zensor Pico - £120
DALI Zensor 1 / Spektor 1 (Small speakers, but 24cm deep so need a little more desk space) - £150
Q Acoustics 3010i (£150) or 3020 (£120), slightly deeper again, but also good VFM
Amps
Denon PMA-30 - £300
Yamaha WXA-50 - £350
NAD D3020 v2 - £350
Then later on a sub:
BK Elec Gemini II £200
Definitely look for bargains, I bagged a TEAC A-H01 (Amp + DAC Desktop combo for £199 which was half price).
In total I've spent £600 for the speakers/amp/dac/sub and haven't regretted it once. Of course there is better sounding products, but not unless I spend a lot more and give up more desk space than I have.