Tried looking for past experiences, but no luck.

Drivers side original armrest now just moves between fully up or fully down sat on handbrake, locking mechanism seems busted.

Any thoughts out there on repairs and potential costs? Lago Grey Ebony HSE auto, 19" alloys, privacy glass

There should be a rod in the arm rest that attaches to the winder wheel it may of come lose, if you can't fix it
you could always give Dan our site sponsor a message for a quote on a new one  BETTER looking half of the famous Twinlanders
The wanna be other half - http://www.freel2.com/forum/member-carriec.html

Cheers, there is a pin that has sheared inside, have emailed sponsors to see if its a part that can be supplied,

n Lago Grey Ebony HSE auto, 19" alloys, privacy glass