Yamaha DTXpress/DTXplorer/DTXtreme

Can anyone recommend a replacement pad for the old Yamaha DTXpress 
(mine is about 4 years old) so that I can do rim shots?

Also - any tips as to how to use it with the head?  I understand I 
will have to program new snare sounds and use two ports from a stereo 
cable to interface it?

Any advice is sincerely appreciated, and you may email me direct if 
you wish at tdjme@...