gmp
 
I think the only 64 bit chorus in Sonar is BT Analog Chorus CH2S-3.dll

Any others?

 
The Sonitus Modulator and MultiVoice Chorus/Flanger are quite useful.

Is it ok to use the 64 bit DX pluggins that I find in the folder? Does it look like they'll be phased out?

DirectX is a "zombie" format - it died a while ago, but still lives. Some DAWs don't support it at all any more, others do. SONAR continues to support DirectX and I don't see that changing for at least a while. Sony, Samplitude, and Acoustica among others stlll support it.

The 64bit DX plug-ins should work OK. But as Craig indicates, it is a legacy format.
 
In addition to the Sonitus and Cakewalk chorus plug-ins (both DX by the way), there is a chorus included in TH2 Producer.
 
There are plenty of free chorus plug-ins on the net. Acon Digital Multiply is a nice one.

Every time i see a thread like this i sorely miss my DSP bundle. i have moved on but i would buy a 64 bit version in a heartbeat

FWIW, I've never been able to get .AX format DX plugins to work in a wrapper/bridged fashion, only .DLL.  It's a tradeoff.