After a lot of research we have an updated list of working Japan Proxy Servers for you:

194.250.131.225:80
85.206.12.80:80
89.97.181.250:80
63.251.57.112:3128
207.44.255.171:80
208.69.235.134:8080
148.233.239.23:3128
200.226.137.11:80
207.44.255.162:3128