Coffeeshop 137 is just off the top of the main map. Walk past Siberie on the main map along the Brouwersgracht. You have to cross from one side of the canal to the other a couple of times because of a lack of bridges. Just follow the canal and it will bring you to 137 on this map.
Haarlemmerstraat also leads to this area. Just walk past the various Barneys and as you cross the Prinsengracht the street name changes to Haarlemmerdijk. The first left turn is Binnen Oranjestraat, which leads to Relax.
Heading north up Marnixstraat past Bronx and 't Keteltje will bring you onto this map.
It's worth noting where the bridges are in this area because there are some wide canals with few crossing points.