c# wrapper for Barclays MPI payment gateway API

I am looking for a simple wrapper that will allow an existing application to make payment through the Barclays MPI payment gateway. We currently rekey each order into the Barclays system and wish to automate this. The requirement is very basic in so far as it is just customer details, amounts and the actual payment details. These will be passed in (no preference of how) and the wrapper will then call the service and return details. This would need to be able to process payments (adhoc only) and refunds. There is an attached document that details the API and I may be able to provide a sandbox environment on another account. However, I am hoping that someone has already completed this work.