This post we provide a list of socks4/5 proxy from the U.S. may be useful for you
Good Socks 4 proxies:
174.101.124.57:31807
24.166.86.74:7685
24.44.106.185:25464
65.34.57.147:1815
67.168.53.160:1158
67.191.94.32:8987
67.20.26.228:1971
68.84.14.93:8911
69.113.197.222:16375
72.200.185.198:4357
72.91.76.153:17805
76.125.250.45:3162
76.18.177.104:39283
98.148.131.76:1346
98.237.30.113:3134
98.253.246.167:53866
Good Socks 5 proxies:
24.166.86.74:7685
67.191.94.32:8987
68.84.14.93:8911
72.200.185.198:4357