Paper Direct Debits via GoCardless integrated with Etapesty

Hi

We currently use GoCardless for Direct Debits which are set up via an Etapestry DIY form on our website. Not all our supporters can access this so we want to produce paper based Direct Debit forms for people to complete send back to us and for us to then enter onto Etapestry and autoprocess from that point onwards. Is anyone else doing this? I have been in touch with Blackbaud and GoCardless but apparently we have to upgrade to GoCardless Pro/Advanced which is not too much of a problem, just slightly higher percentage per donation but would be worth it. HOWEVER they are also saying we would have to pay and additional £150 a month to be able to do this! We are a small charity and this would be completely impractical. Has anyone else come across this? Is there a better way of taking paper based Direct Debits which can then be autoprocessed via Etapestry? I feel like I'm going round in circles between Blackbaud and GoCardless and getting nowhere!

Any advice would be very much appreciated - thank you!