Ok, I am brewing my Scottish Barley Wine. I know there is no style for it, but the recipe is based on an English barleywine, but with a Scottish flair.
21 lb Golden Promise
1 lb Peat malt
1 lb UK Crystal 60
2 oz Magnum 120min (I know American hops, but couldn't find a good bittering UK hop)
Hoss, that's no English Barleywine, it's an American Barleywine with ALL those hops added... You're looking at about 115 IBU there... WAY outside the English BarleyWine style... English BarleyWine's have 30-70 IBU's...
If you want to actually MAKE an English Barleywine, then drop the Magnum hops. You could also use Fuggles for the flavor addition, at 20 minutes (1 ounce), and shift the 15 minute EKG to 5-10 minutes. That would give you about 48 IBU (depending on the AA% of the hops you get)... You could also try using Target hops for bittering (it's included in info about the English Barleywine's)... Those have a bit more AA% in them than Northdown hops, typically. Switching to Target hops, for a 60 minute boil, would get you right about 50 IBU. Unless you have made an English Barleywine before (doesn't seem like you have yet) with more IBU that you really enjoyed, I'd aim more for the middle of a style's range for a first time.
I would try 1/2 pound of the smoked peat malt for a start. Unless you've tried an English Barleywine that you like that has ~4% of the grain bill in smoked peat malt.
I also agree that you could use a Scottish Ale yeast, like Wyeast 1728 for this. Actually probably a better idea than the London Ale III since that tuckers out around 10% ABV... You could go to 12% ABV with that recipe (and the right yeast)...
I'd also be interested in knowing your mash schedule/plan for this one...
Also, keep in mind, Scottish brews are historically LOW IBU brews. So if you want to make a Scottish Barleywine, you would want LOWER IBU's, or at least in the bottom 1/3-1/4 of the range. Not where you started...
Gor your statement (in bold above) about not finding good UK bittering hops... You couldn't have looked very hard. Beer Smith lists 8 UK hops for bittering (only) with three more that are listed as 'both' (aroma/flavoring and bittering)... I actually like Target for bittering, as well as Northdown... You COULD use EKG or Fuggles for bittering if you wanted to. You'll just need to add enough of them to make the IBU's for the style...
I would suggest running your recipe through some software so that you can actually SEE how many IBU's you're going to get with your hop selection, schedule, and amounts... Otherwise, you could make something that will make your face implode due to high bitterness... Or not even be drinkable in December, of this year... Maybe it will be in another year, or three...