The sources has revealed that the replacement opponent will come from Japan but will not be Odaira, which brings us to a rather small short list of WBA ranked Japanese fighters at 105lbs or, potentially, 108lbs, which interestingly doesn't actually including Odaira.
The short list features former world title challenger Ryuji Hara (20-2, 11) [原隆二], who had been pencilled in to face Knockout back in October in a bout that was slated for a Japanese venue and a chance for Knockout to make an international debut, with Hara ranked #15 at 105lbs. It also includes former world champion Ryo Miyazaki (24-2-3, 15) [宮崎 亮], who is ranked #5 at 108lbs and we really can't see him taking the fight at Minimumweight following previous weight issues, and the exciting Kenji Ono (11-1, 6) [ [大野 兼資] ], who is ranked #13 at 108lbs. Ono has never made the 105lb limit but could possibly manage it for a world title fight and would be a fun opponent for Knockout , especially considering his FOTY contender with Jun Takigawa ealier this year.
One other man who we've ignored from the short list is #5 ranked Minimumweight Tatsuya Fukuhara (17-4-6, 6) [福原 辰弥], who fights in November and would likely not have the time to prepare for Knockout given the small window between fights.
Of course, with the WBA being the WBA, we may see a wild card entry put into the rankings in the near future, such as Riku Kano (10-2-1, 5) [加納陸], who actually makes sense for the bout given his prior association with Thailand and the WBA. For now those it's a case of waiting until an announcement is made.