Drupal payment modules without "product, "

I have a Drupal 6 website where I need to handle payments. Ubercart doesn't fit well (I think) - it looks like a huge overhead of cart, orders, products, etc.

That is a website (views+cck powered) where customer creates node with some cck fields, the node goes through some workflow, and at some workflow stage the operator "assigns invoice" to the node (that's actually cck selectbox with status "inv开发者_运维技巧oice ready" + cck textfield "total amount". The customer sees "Pay this invoice" link in his views, and after clicking this link he should be given a set of links to available payment options, like paypal/gcheckout. When customer processes the payment, the node gets new status (again, in cck selectbox - "invoice was payed")

So, I'm seeking for some generic payment modules for Drupal, that provide just several hooks like "payment_done()" which I can implement to set my cck fields. Do you know any?

The only generic payment module I know of is Pay which still is in alpha. It's a while since I last looked at it so it might be usable now.

Else your best chance is to find a module for the actual payment provider you're going to use, many have a module that will allow you to do basic payment handling with various hooks etc.