The coin mechs are pretty much completely standardized in terms of form factor. Any door you buy with a mech "built in" would just be a standard mech hanging out in the spot designed for one ready to be changed out for whatever coin you want it to take. The only issue would be if the coin you want it to take is REALLY big - some coin slots aren't big enough to take things much bigger than a US quarter or so.
I know you can buy coin mechs for various coins (probably including pound sterling), or if you really had to go nuts, a coin comparator would work for anything. I currently have a Pump it Up machine taking 100 yen coins

I'm guessing you can buy coin doors that'll come including coin comparators, but mechanical mechs tend to be MUCH cheaper.