What would you like done?
Create a plugin to integrate Discourse with 2checkout and enable paid memberships as follows:
Free subscriptions for all categories except those chosen as paid categories
Monthly subscriptions for any category
Yearly subscriptions for any category
User will be kicked from the paid category if did not renew their plan. Reminder email notifications (7 days, 3 days and 1 day) before the expiry of their plan. Should be based on 2checkout only.
When do you need it done?
Within 7 days.
What is your budget, in $ USD that you can offer for this task?
200 USD + Bonus upon earlier successful bug free delivery.
I think you might have luck in the $2000-$5000 range, but that too is well beyond your budget. You might see if the 2checkout people would be interested in helping to fund or develop it.
Might Patreon or Memberful be options in your country? Paypal?