Is There Paid Membership Management for Modx?

I am looking for a paid membership management extra for modx. I remember Mark's SubscribeMe but that is no longer supported. Does anyone know of any others? Third party membership management tools cost a great deal of money and for my clients, that isn't usually an option as a result.

Thanks!

SubscribeMe is the only one I can think of - http://rtfm.modx.com/extras/revo/subscribeme