I'm a hand-sweating, string-killing machine myself... I never did extensive research on uncoated rounds in order to find which seemed to take more time to die under such hostile conditions; I simply switched to flatwounds (a move I decided to make since I found I like their tone, and could afford to because I'm a hobbyist - I doubt I would not keep a bass with rounds if I played out more, but they'd have to be coated) and am currently trying out tapewounds. I doubt uncoated rounds of any make and model could last as long as Elixirs; I'm willing to be proven wrong of course. Anyway, I just thought you could either be vaguely interested or mildly amused by the mention of domestic steel in the Skull product blurb.
Now, back to coated .11 strings.
BassStringOnline (in the US) only has a DR Black Beauty of that gauge available as a single:
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but DR make some of their coated models, clear (Bootzillas but not Dragon Skins) and coloured both sober (Black Beauties, Red Devils and Cool Blues but not Silver Stars) and flashy (Neon Green, -Orange, -Yellow and -Pink but not others) in 50-70-90-110 sets (BBs even have one with a tapered E).
Other two brands of interest that make heavy sets with those exact gauges are Cleartone Strings (which apparently aren't coated proper but "treated") and Aurora (in a vast array of colour options, including clear). (Italian brand IQS has coated offerings which do not include those gauges, and uncoated ones which do.)
If you definitely want a coated .11 and don't want the black Pyramid I linked to above you might find one of these sets somewhere in Europe.
If the rest of the gauges are too heavy and/or unbalanced for your taste and don't want to get an entire set for only one useful string, you might try asking
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Cleartone or
Aurora, and see if they're willing to put together a custom set and sell it direct (I'm pretty sure, from TB member reports, that at least the latter will be).
EDIT: another Italian brand, Galli, makes a
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