Much more viable to just get another wheelset. You can shop very carefully and hard for disc hubs on the cheap; but you aren't, in all likelihood, going to be able to re-use your spokes (which is not really advisable anyway) because of lengths. So by the time you've bought hubs and spokes, relaced everything and trued 'em up, you'd have been ahead buying the wheels. Decent disc wheelsets can be found very reasonably now - - especially 26".
And no, I'm
not even going to tell you about these little doohickeys:
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