You could use HikaSerial in order to simplify a bit the integration but that will still require a HikaSerial plugin to be developed since there is no standard webservice APi for that. Each service has it's own way of doing things.
If you can't develop it yourself you could have it developed by a developer.
If you want, the developer of HikaSerial, Jerome, could develop it for you. If interested you can contact him with the documentation of your webservice so that he can give you a quote at jerome at hikashop dot com