Custom Wordpress plugin required

I have a Wordpress website that has an additional table to hold the addresses of about 100 worldwide distributors. Within the website we use this table to populate a page with a Google map. Visitors can select a country from a drop-down list and display the address of the local distributor for that country or region.

We need to develop a plugin for the administration side of the Wordpress installation that will allow us to update / edit entries within the existing table and also to add new entries.

The table has 14 fields of information - text only.

The plugin has to append a link in the menu area of the Wordpress administration page which will take the user to a page to manage the entries in the custom data table.

Specifically we want to be able to add a new entry, edit an existing entry, duplicate and existing entry to amend just a few fields or delete an entry.

We already have a system to update the table outside of the Wordpress installation but would like to bring it into the Wordpress administration area - it makes it easier for the client.

I want this job completed by this Wednesday morning, 15th June UK time!
I will be looking to award the job by 5pm UK time on Sunday 12th June