Want to add on to what rainbow_smile said on
http://japanauction.byethost11.com/ (his name is Kairai)
Yes it's true Kairai's charges are more expensive but it's because the middleman business is only handled by him , unlike Celga (that has customer service staff in both USA & Japan)
In addition , Kairai resides in Sapporo and not Tokyo but he knows some contacts that're living in other prefectures
Despite this , I've been satisfied with Kairai handled my fanclub related matters over the last 6 years , especially when comes to helping me to ballot tickets through the fanclub
Beginning of 2017 when I went back Japan , same as before , I requested Kairai to mail my concert ticket to the hotel I stayed & he did it without hesitation . He also mailed me a belated birthday gift to me as well which was so nice
Lastly to add on , here's a list of sites Kairai can help you to buy concert tickets if you're not in the fanclub (excluding Yahoo Japan auction) ->
http://japanauction.byethost11.com/tickes-orders