Mariano,
There is a company from Argentina on ebay which sell brands new hoses for many vintage vehicles:
https://www.ebay.com/str/LNF-BRAKES
I think this set would fit an F15A:
https://www.ebay.com/itm/FORD-TRUCK-...7/362626618238
This would solve your problem of not being able to buy from abroad at the moment.
