Here, Twinwillow, are some places you can get Horlicks:

http://www.madeinbritainltd.com/hormalpow14o.html

http://www.foodireland.com/Merchant2/merchant.mvc?Screen=PROD&Product_Code=522106&Category_Code=beverages&Product_Count=9

The first one is a British site, the second is Irish.

Go to amazon.com and search for Horlicks. They have several different ones available. Don’t know if any are American, however.