I was in the Caithness Factory shop just yesterday - I managed to sneak in for 2 minutes before they shut, but did have the opportunity to speak to a knowledgeable member of staff.
I even saw a few newly made Limited Edition "Whitefriars" Caithness weights. There are images on their site (link below).
They still have the original monk canes and are CURRENTLY making weights including a sliver of the cane.
I was given the catalogue containing the images of the 2012 weights, I have perused the website but cannot find any of the designs which may have been produced prior to 2012, but I an now thinking that your weight is one of the new ones. I did ask the lady about neodynum weights with a wfs cane, but she didn't seem to know what neodynum glass was... we really only had 2-3 minutes.
Linda Campbell is the amazing lampworker for several (if not all of them), she trained with the superlative Allan Scott - which would account for my muddling the quality of the lampwork with that of Paul Ysart.
I wouldn't confuse Allan Scott with Paul Ysart though. Allan wins, no contest. (IMNSHO)
Anyway, here's a link to the Caithness website - I would recommend contacting them to ask about your weight.
Perhaps not a "museum piece" just
btw - is this your sale?http://www.ebay.com/itm/Rare-caithness-whitefriars-neodynum-glass-paperweight-a-one-off-bright-new-day-/200829497776?pt=UK_Art_Glass&hash=item2ec25ef1b0