Best cartige for the money and why?

Best for you or best for me ? 
For this reason there is no best cartridge.

If you ask why some MC cartridges are better than others you will understand some of them are unique, this is a prime example of relatively cheap and unique MC called "Direct-Coupled", printed micro coil located right above the cantilever, this is the one with very dynamic sound. Audio-Technica engineers are inspired by this technology, as the result we have new ART-1000 (a very expensive modern MC made under impression of Victor Direct-Coupled design). 

Shibata stylus invented by Victor Corporation.
MC1 has Beryllium cantilever. 

As you can see in the catalog there are more great models, look at Victor X-1IIe (Titanium/Elliptical) MM - this is a great alternative to nearly all modern MC you can buy under $700. And the top Victor MM model is X-1II (Beryllium/Shibata). 

Regarding some great classics i would recommend Dynavector KARAT 23RS Ruby with MicroReach stylus, they are normally under $700 in mint condition. More about Dynavector carts in my thread here. 

I don't have any specific recommendation for lower cost cartridges; I generally like the more modestly priced examples of Dynavectors that I've heard.  

I have heard the ART 1000 that Chakster mentioned above.  At $5,000 or so, it is actually one of the cheaper super cartridges.  I really like that cartridge--it is lively, detailed, and very dynamic sounding without being excessively sibilant.  If I were in the market for a $5,000 cartridge (I am not, I already have a Lyra Titan and a Transfiguration Orpheus L), that would be under consideration.

The Hana SL is $50 more than your budget, but worth it and a solid performer in that price range.

This cartridge has been around for awhile. 
https://www.lpgear.com/product/ATC01.html

It's been  a popular choice for value a MC for years.

Plenty of reviews out there.  

Another good value MC cart is the Denon DL-301 MKII (around $400).