Stating that your accordion has been stored in a loft for thirty years will have set off alarm bells for many/most of our members. Even when they are stored well, accordions are prone to developing irreversible problems.
The person you are looking for could well play in Folk Clubs, as the musical range of an 8 bass accordion restricts it to playing very simple tunes. He or She would need to be familiar with the insides of an accordion.
The $64,000 question ............ What's it worth? I know you won't like the answer to this question ....... very little !!! You would be lucky to get £30 for it, and only then if it appeared to be a simple repair.
This video is called Oergeli Karusell Ruedi Wachter.
At 050 he shows a tiny piano accordion with some bass buttons. It looks to be smaller than the Hohner Mignon.
Can anyone zoom in on the video and see what brand or name is written on that tiny piano accordion?
Perhaps you have all seen this video with Ruedi Wachter demonstrating a beautiful collection of accordions: