Custom Pledge Module/Plugin?

I'm looking for a plugin that can do something similar to this page: http://www.cathouseonthekings.com/docs/ ... p?aid=8895
As you can see, there is a 'Monthly Pledge' textbox with an amount. We would like to have something similar to this, giving the users the ability to enter in a custom amount if they don't want to pay the default amount.

Look for something like this:
FREE:
Payflow Pro Ultimate - On Page With Recurring Profiles, OC v.1.5.x. - 1.5.6.4:
http://www.opencart.com/index.php?route ... n_id=16067
FREE:
Charity donation and admin, OC v.1.5.5, 1.5.5.1, 1.5.6, 1.5.6.1 , 2.0.1.0, 2.0.1.1, 2.0.2.0, 2.0.3.1:
http://www.opencart.com/index.php?route ... on_id=5538
FREE:
Donations(v2.5), OC v.1.5.1, 1.5.1.1, 1.5.1.2, 1.5.1.3, 1.5.2, 1.5.2.1, 1.5.3, 1.5.3.1:
http://www.opencart.com/index.php?route ... on_id=3275
PAID:
Paypal Recurring 1.5.x, 1.5.1 - 1.5.6.4:
http://www.opencart.com/index.php?route ... on_id=8083
PAID:
Recurring Cost Order Totals, OC v.2.0.0.0, 2.0.1.0, 2.0.1.1, 2.0.2.0, 2.0.3.1:
http://www.opencart.com/index.php?route ... n_id=22687
PAID:
Real Free Trial Subscriptions, OC v.2.0.0.0, 2.0.1.0, 2.0.1.1, 2.0.2.0, 2.0.3.1:
http://www.opencart.com/index.php?route ... n_id=23067
SEARCH:
http://www.opencart.com/index.php?route ... =recurring
Good Luck
Ernie
bigmax.ch/shop/

WOW! Those are some options! Thank you, IP_CAM!

I'm afraid you need custom work. All (recurring) pricing is preset in the admin section and can't be changed by a customer except for choosing the ones you created. Even if you find an extension that would let a customer enter a price for a product, it's not going to be a recurring payment!