Hi, Steve: re. the steering wheel adaptor, it might be an idea to contact Mike Knapman, longstanding Club member, who has a myriad spares secreted around his house and lock-ups.
Mike’s contact details can be found in the Club Yearbook.
David Cornwallis is the person to contact re males steering boxes. The Palm Beach box is different from the K’s L’s etc.
His email info@davidcornwallis.com.
I cannot help on the steering wheel . The original steering wheel on a PB is not Blumels. Probably a proprietary one from a Vauxhall in period.