HI Steve,
We (LInk2Systems) have an EDI solution that is a monthly subscription. We bypass the VAN by pushing the file layout to the SFTP folder of the customer/vendor or allow vendors to pull from an inhouse SFTP folder.. This solution is not transaction count based or byte based, but a monthly affordable charge that can send files hourly/daily/weekly/monthly.

Please let us know if there is any interest.

Best,
Brian