Where to find replacement cones preferably with seals

[Carlton_gang]

Like the title says, I'm struggling to find replacement cones for a variety of hubs, road and mountain bikes, the recurring theme being that they're all old unsealed units. I was wondering if you can get cones with rubber seals a bit like on some shimano hubs (I have a set of shimano 105sc hubs like this with a very simple seal attached to the cone which seems to work very well). I have tried making some makeshift seals with o-rings, but these are fiddly and annoying, and I was wondering if you could get any with generic rubber seals, as I hate taking hubs apart and servicing them with the interval required with unsealed hubs.
Have also posted in the road section because it concerns both road and mountain bike hubs.
Thanks in advanced.