Hi Cory, I know of but have no experience with MerchantE and Solupay who each have an ePay solution. MerchantE has ACH. Not sure if Solupay has ACH. Both have customer service issues that I am aware of.
SCSCloud.com has an ePay solution that works very well from Sales Orders and Invoices. They have an ACH solution coming before the end of the year. Hope that helps!