Hi, i'm not going to sell you anything, recommendations are the way we will go.
I've worked for twenty years in the industry and have had my own store in recent past but i've been into this for longer.
I agree with the first person replace that Harman Kardan receiver. It's going to be the weak link in any chain because even if you through in some fabulous speakers, you will still be missing out on the ability of conveying music.
Here's some used pre-amp recommendations that won't break the bank and offer balance to your system. Note: Models no more than 3 to 4 years old as these will generaly offer updates : Rotel, Exposure, Arcam, Consonance, Monarchy Audio, MSB Technology, Opera Audio, Prima Luna, Rogue.
These brands provide some of the top values for a well intgrated system. Some are pre-amps are solid state and others use tubes to add some in most case musicality. The solid state in this price point you can afford looks closer at the detail end of the spectrum.
For now I would be inclined to sway towards a hybrid/tube design because of your front end(Sony CD Player),. I've listened to a few pre-amps and you want to match well. This is where i've seen people start flying through money and products.
This is a big part of the problem; often voltages are mismatched between pre-amp and amplifier and no synergy. Keep in mind that all. Other than that listen, ask and read between the lines.
If you have heard speakers you like this is a good start; however, listen to a few more so you don't find yourself regretting the next week or month. Someone mentioned Usher and they are newer to North America but have had one of the best known speaker designers involved with their products. You can find awesome deals on-line used on both the book shelfs and smaller floor speakers. They have also been one of the best reviewed speakers in the last four or so years. Oh ya! Looks to die for in your price range.
Have a listen to Dynaudio, why? They have some of the very best components in their speakers period. Dynaudio introduced a new line in their speakers above the Audience line. You will find now that the Audience speaker line reduced and this makes them one of the hottest buys out there today period. Although the tweeter is not the Dynaudio Esotar it is still very smooth and once broken in the mid-range is tops period in the price point.
If your goig witha book shelf do not rule out a powered sub, now or down the road. If you sub is of good quality it will integrate and open a massive sound stage and boogie factor. The internal amp in the sub will take the load off other amp and put it's responsibility on the mids and highs. Now you won't have to tax you amp so hard with the main speakers and this gives more sense.
If you move you can still take the sub and adjust for the next room. Some recomendations for subs: SVS, Def Tech SuperCube I, HSU, James Loudspeakers, Rel and Velodyne. Go above the Velodyne entry level stuff, it's more musical; as I find the entry leans more towards home theatre rumble and not as musical.
Note: If you can get a remote with it great, it will save time going to the back to make adjustments. Easier to tell how it will sound from your seat without going back and forth. Don't give up the musical sub though because this will make great to awesome.
I'm sure on your side of the border you will find one the mentioned brand pre-amps for around $500 used. For the sub with taxes $800 with taxes and the speakers that leaves $1200 for the speakers. Focus on that for now and don't worry so much about the CD being updated for now, or the amp. Things should turn up a few notches as you will see.
Last bit, keep in mind the wire being used as you are listening to other systems or components. Short list what you like in the reasonable price range and when can afford, ad it.
Cheers,
Keith