ok, the keyspace would be:
95^6 [completely unknown characters] * 10 [possible positions for "3"] * 10 [possible positions for "4"] * 11 [possible positions for "5"] = 808601079687500
assuming all the rules you mentioned apply and all the suspected numbers are in the password. (actually a little less because for example "3" and "4" cannot be at the same position at any time obviously)
On a single 1080 you can calculate about 4203 H/s for a bitcoin wallet, I think that has the same algorithm as litecoin. (see https://hashcat.net/forum/thread-5762.html)
Running through your keyspace on one such device would take about 808601079687500/4203/60/60/24/364 = 6117.3 years. Even with slight further reductions and a load of GPUs it would take years to recover the password.
95^6 [completely unknown characters] * 10 [possible positions for "3"] * 10 [possible positions for "4"] * 11 [possible positions for "5"] = 808601079687500
assuming all the rules you mentioned apply and all the suspected numbers are in the password. (actually a little less because for example "3" and "4" cannot be at the same position at any time obviously)
On a single 1080 you can calculate about 4203 H/s for a bitcoin wallet, I think that has the same algorithm as litecoin. (see https://hashcat.net/forum/thread-5762.html)
Running through your keyspace on one such device would take about 808601079687500/4203/60/60/24/364 = 6117.3 years. Even with slight further reductions and a load of GPUs it would take years to recover the password.