You can buy it from videoguys.com.au in Melbourne for $749.
I don't think you'll gain much if anything compared to the MC encoder for usual mpeg-2 encoding for DVD. Best way to get good mepg-2 encoding is straight from the Vegas T/L. To do that with Procoder you'd have to frame serve from Vegas.
The batch encoding in Procoder is a nice feature however you can do the same with Vegas and Peachrocks Multirenderer. The later we use very intensely and it's a real money maker for us.
The one thing that the MC encoder sucks at is mpeg-1 for VCD. Get TMPGEnc from Pegasys for that. The mpeg-1 only variant is free.