There are a number of people who can rewire the RB250 relatively quickly and inexpensively. Do a search here in the Turntables and Tonearms category and you'll find them (one of the better known uses the heading "Cardas rewire service"). IMO, unless you have some experience with micro-electric assemblies, it isn't a DIY job.
That said, you may also want to consider a new arm. There are several that are much improved over the old RB250 and much easier to properly set up. Moreover, the age storage location of your Planar 2 means the bearings could have some issues. I rebuilt my Planar 2 way back in the day and responded to a post several years ago with some tips here: https://forum.audiogon.com/discussions/back-to-tt-after-24-years/post?postid=702506#702506.
On the dustcover decal, you can contact Rega to see if they have a spare. Otherwise, you may be out of luck - that is a seriously old decorative element now.
Good luck & happy listening!
That said, you may also want to consider a new arm. There are several that are much improved over the old RB250 and much easier to properly set up. Moreover, the age storage location of your Planar 2 means the bearings could have some issues. I rebuilt my Planar 2 way back in the day and responded to a post several years ago with some tips here: https://forum.audiogon.com/discussions/back-to-tt-after-24-years/post?postid=702506#702506.
On the dustcover decal, you can contact Rega to see if they have a spare. Otherwise, you may be out of luck - that is a seriously old decorative element now.
Good luck & happy listening!