I just re-read your post, and noticed that you're driving the speakers with a Jolida 102b. That's a 25W amp.
Given that, I would consider Coincident Triumph UHS (monitor speakers). They're available used on the high end of your budget, maybe slightly higher ($600). But they have the sensitivity to handle the music you listen to with the Jolida. An alternative would be some used Klipsch speakers (you can find several models under $500 used).
If you sell the Jolida 102b and either upgrade within the Jolida family (ie, 302b) or switch to a high-value integrated (such as the Onkyo A9555 that's been getting a lot of press), then you'll find your options in speakers considerably wider.
Michael
Given that, I would consider Coincident Triumph UHS (monitor speakers). They're available used on the high end of your budget, maybe slightly higher ($600). But they have the sensitivity to handle the music you listen to with the Jolida. An alternative would be some used Klipsch speakers (you can find several models under $500 used).
If you sell the Jolida 102b and either upgrade within the Jolida family (ie, 302b) or switch to a high-value integrated (such as the Onkyo A9555 that's been getting a lot of press), then you'll find your options in speakers considerably wider.
Michael