I think you can find a few copies of the sub cover on Ebay, I bought one last week. But yes, it seems to have been oddly rare - the Forbidden Planet I get my comics from never got that issue in, for some reason.
I bought mine from A Place in Space, which is my usual eBay seller. They had 9-10 copies of each cover, IIRC, though the main one sold out in about a day. They tend to list comics as (eg) 27A for the main cover and 27B for the sub, so a simple search for "Friends Forever 27" doesn't always bring them up. I'm never quite willing to trust eBay searches anyway! It is a bit strange, though -- there's still the odd UK-based copy of FF 28 floating about, and you'd think that one (Luna/CMC) would be more in demand.
Has there been another hiccup in IDW's supply chain this month? I ask because I was going for main series #44 in the RI cover, easily found the regular and ROM covers in UK stores, but only a hooffull of RI covers, all from the Americas. Hoping this is a one off glitch, as I like the pastel style used on the RI covers more these days, and while #44 isn't a great loss, next month's with the Vemon'esque Nightmare Moon is one I'll be gunning for.
They had all three non-exclusive covers (normal/Sub/RI) in the Forbidden Planet in Bristol, though that's traditionally been one of the best branches for pony comics. I bought the ROM cover (not a fan of ROM, I just liked the sci-fi theme) but I think there were 2-3 of the Sara Richard ones in stock.
I'm not sure if anyone is still looking at this thread but does anyone know how much any of these comics are still worth? I have a quite lot and want to offload them now but wondering if it's worth doing a bulk lot on eBay or somewhere or just recycling them as most charity shops don't accept paper comics nowadays.
I'd be interested in picking some of these up if you're wanting rid of them. What issues are you looking at off loading?
Let me take a look in the next few days. They're all bagged and boarded and in comic book boxes and in pretty good nick but stored in the loft at the moment. I'll get a few pictures and issue numbers and pop them here soon. (Admittedly, I think some of them are rarer but I'd really prefer to get something for them rather than toss them.)