The process to "outrig" a sgian would be quite elementary. Spring clips are available at wilderness outfitters and Tandy leather. A pop rivet would be the crudest way to attach it, but quite simple.

The clan crest in an appropriate size might be a bit more difficult, as I imagine one much larger than a US/Canadian quarter would be overwhelming on the hose.

Perhaps finding the source for crests in the size mean to fit IN the handle of a sgian might work... I wonder if Gaelic Themes could assist.