NT31c to PLC5/25

I would like to add an NT31c to an existing AB PLC5/25 for monitoring purposes.
The PLC has on it 2 x DH+ ports available.
Has anybody done similar?
Is there a converter available?
Should I just buy an AB HMI !

Any help/advise would be greatly appreciated.

Cheers

Fred

I think converter might be cheaper.HMI with DH+ are expensive.
I saw converter like that somewhere but I cant remember where.
Check here they have HMI with DH+.I think its cheaper then Omron NT31c
http://web1.automationdirect.com/adc/Shopping/Catalog/Operator_Interfaces/EZTouch_Panels/EZTouch_Units_(all_sizes)