New speakers Required(5.1)

Hi there all!

I have a problem.

I have a denon avr 2803 which is a great amp.

I have had to sell various units in my set up and now have 1 centre speaker(mordaunt short) and 2 front mission speakers which are quite old.

MS 905i

Missions are all black not sure on models as i have wall brackets behind them.

I also have no subwoofer although i had a gale one which worked well.

I was also considering replacing the amp but dont wont too unless i can get the same quality in a new amp.

I see richer sounds are selling a pioneer set up with amp for less than £200-but think i may be disapointed.