They pop up on eBay a few times a year. Also try getting in touch with Jon at National marine - suspect he has one knocking around. Failing that keep an eye open for a knackered old 5.4 with a useable console you could take out and refurbish.
I have a genuine sea rider console. Has the vinyl seat which is in good condition apart from the wooden base, bit dodgy. The console has a steering helm and cable fitted. Does work but doesnt look that pretty lol. Heres my mobile number. 07790 638172