The moped junkyard is one of the last places to look for parts, since they have high prices as a general rule.You can go to the buy sell forum on this website, and search and/or place an ad that you want to buy a complete Sachs air box/ filter assembly. You can look on ebay too. Find someone on ebay listing a moped with a Sachs engine that has it listed as pick up only. Ask the seller if it has the complete air box/ filter assembly, and if they would ship that and maybe a few other parts you may need if you were to bid. Ask to ship the whole engine if you can spare the cash to ship it.