vBulletin 5 Modification - Invite Only Registration System

Good afternoon! I am looking to hire a developer for a one-time vBulletin 5 project. I need my forums to have an invite only registration system. It does not have to do everything that is listed here ([login to view URL]), but it needs to at least do the following: New registrations requires invitation code. Members can invite their friends via forum. A tab and/or in their user profile that shows who they invited, who they got invited by and when. In ACP you can choose how many invites a usergoup can have every week, month, year. There is already a similar modification for vBulletin 4 ([login to view URL]), but I would like to upgrade to vBulletin 5 and cannot do so unless I have an invite only registration system. If interested in taking on this project, and if able to complete this project within the next 1-2 months, please contact me with a quote (which may be above the price range I've selected, if you can justify it). Thank you!