If you are looking for a cheaper alternative the ZE32GK gasket kit is also available without the brass.
The 404 Repair Manual - Section 07.2 Covers 17 Pages of Carb Rebuild Information, with detailed drawings and instructions. You should have this reference prior to trying to rebuild. The paper diagram that comes with this kit is NOT expected to replace the proper technical information.
This kit is an ok kit, but by no means worth the money. My kit only had one set of gaskets and a single extra gasket of the "premium" style, the crush washers were a poor fit, the accel pump arm didnt fit on my ball on the throttle crank, the Exploded diagram showed o rings on two sets of jets but only one set of o-rings included. The exploded diagram was the only form of instructions with no legend as to what parts went where. The are a couple pieces that will fit multiple places so if this is your first carb rebuild take detailed pics before you disassemble. You would be better off just getting gaskets and a set of o-rings. Or maybe just a new carb, most carb kits are $30 or so, but there is definitely a supply and demand at work here. ******************************** 3/1/16 EI Update: Andrew we have updated the photos and description of this kit. The technical diagram that comes with the kit is NOT expected to replace the 17 pages of detailed rebuild information in the Repair Manual. Anyone attempting a carb rebuild should have this information. In regards to carb kit cost......We will have to respectfully disagree. A factory kit with all of the brass jets, valves, and pump.....for $30, for a 50-60 year old carb? A cheaper alternative is the $18 Gasket Kit, if you do not need the jets/brass. Thanks for the feedback, I have emailed you direct as well. Cheers - Scott