Hi Elliot,
I don't personally keep kosher. Here it isn't hard to keep kosher though, seen
as you have to go (a little) out of the way to not keep kosher. Regular
supermarkets and most places are kosher. Recently I have been buying South
African wine from a non kosher supermarket chain which isn't kosher (both the
shop and the wine), which is unusual actually.
The best thing I could recommend is buying some drinks specifically from
Israel, weather by another person visiting/living here or by buying on the
internet.
A good website to check out, though I'm not sure if they have other alcohol
besides wine:
http://www.israzon.com/
The duty free shops in our airport are very good too. This way one can visit
our great country also :) For this I would recomend going into this site:
http://www.dutyfree.co.il/english/content/home.html
I know there is a new liquer shop at the airport, it might be the same one but
just sort of upgraded.