The sgian brew link states it has a resin handle. The sgian dubh does not indicate the handle material, but I suspect it to be the same.

I haven't asked or tried, but wonder if heating the blade would allow the handle or adhesive to soften enough to slip the blades out. Both look to have stainless blade construction. That may be to your benefit. I defer to any knife maker/forger members to chime in for further thoughts.