My vote would be for a better amp and forget about a receiver for those speakers. Then again when the upgrade budget is available again go for a source. Last should cables. I say that because when I had a Bryston B100sst and I tried different sources and had to 'squint' a little to hear the difference between sources. I bought a Meridian G08. Then I upgraded the Byrston to an Octave V70SE. I just recently I put back my original Yamaha cdx1030 (which I did have to squint a bit). As good as the Yamaha seemed then I can't listen to it now. That has been my experience and why I recommended that order.
Good Luck
Good Luck