a new carb is gonna be pretty spendy, i would check with the sponsors for a rebuild kit and just take it to a local shop to have it gone through if it's not completely ruined.
Japan car EPC http://www.epc-data.com/ you can search parts by frame number carb repair pics http://blogs.yahoo.co.jp/kurumanosentakuya/archive/2012/3/25 carb solenoid test http://www.youtube.com/watch?v=2zblyxQzyf4 rebuild kits you can get for example here http://www.minitrucksupply.com/Honda_Acty_HA4_carburetor_rebuild_kit_p/ck-ha4.htm (this one is for a HA4) or directly from Japan http://yokohamamotors.net/store/index.html they are a bit more expensive than the local sites here in Japan, but these sites are only in Japanese. You can try the English version of Rakuten, which is the equivaent of Ebay in Japan and bigger than Ebay here in Japan English with automatic translation, so ... http://global.rakuten.com/en/ just type in the search Honda Acty and a lot of items will show up.Shipping cost to your country can be shown when you select the country where you live This is Yahoo auction Japan, I have set it to Honda Acty, you will probably not understand the Japanese characters, but the pics tell it all, good to compare prices http://auctions.search.yahoo.co.jp/...tab_ex=commerce&fixed=0&ei=UTF-8&pstart=1&b=1 Prices are of course shown in Yen, rough exchange rate as of today Yen 100 = US$ 1.20 or calculate here based on actual exhange rates http://www.oanda.com/