[Amps] Bird wattmeters....

[ec1cwg at dxhunters.com]

Hi all,
Anyone could provide me any good source in US to buy a few spare parts for my Birds Wattmeters (appart of RF parts)?...I know this is not the right place for this question but I´m assuming most part of you are using this wattmeters for your amp´s meassures...Am I wrong?. Thanks.
EC1CT Fernando
E-mail: ec1cwg at dxhunters.com
URE & ARRL member