The Nagaoka MP-200 comes in just under the $500 mark. Can be found on Amazon FWIW. If budget is tight, maybe look at the MP-110 or MP-150 as well.
Here's where you'll have to do your homework to decide if these lower priced models compete though. Initially I was going to mention the MP-300, but its price has soared to nearly $700.
I own the MP-200 and MP-150. Both are very good. They have similar sounds-warm, punchy bass, forgiving of poor music to an extent. They have a great midrange. Top end is good, none fatiguing without being rolled off.
Go with the MP-200 if you decide to go with Nagaoka. Check Ebay, you can save about $100 buying direct from Japan. Thats what I did and I saved $150 on my MP-200.
Both took about 30 hours of break-in to sound great. The first few hours are a little rough. Even Nagaoka recommends break in.
Keep in mind, that these are medium compliance cartridges.
If you want a Moving Coil cartridge, take a look at the Hana EL series for under $500. Read the review on this cartridge.