I think WA is.more like 12,000 miles away
Small Hive Beetle is present throughout Oz, but it thrives in the tropical belt. Go north 100, 200 miles and it becomes a controllable problem... but it's still there.
British bees don't have much Italian (aka Ligurian) in them unless they're Buckfast. We have weather, not climate - Italians don't thrive here unless heavily managed, fed in forage gaps etc.
Even treatment-free hives, like mine, have some varroa. The bees keep the numbers down - that's for another debate, but the 3 mites I found on the baseboard of a booming colony the other day would be 3,000 in a hive of Australian bees. Varroa are everywhere here, like SHB in Oz.