Comment Consider caching instead (Score 5, Informative) 159
Since you're in such a remote area, your visitors very likely also have slow connections at home too. Why not cache the updates instead? You'll be contributing towards a safer, more secure internet.
The first person who downloads them would cause a drain on the network, but at least all future attempts would be served up from your cache. You could even have a spare machine downloading the updates overnight, pre-populating the cache for your visitors, to reduce the burden updates cause during the day.
I've used the instructions here with great success on Squid: http://wiki.squid-cache.org/SquidFaq/WindowsUpdate
Apparently Apple iOS updates can be cached too, e.g.: http://lkrms.org/caching-ios-updates-on-a-squid-proxy-server/