Hardware/topology recommendations for low latency UDP network
Solution 1:
At a frequency of 60 packets per 100ms (600 packets per second) you should have no trouble achieving your goals with simple unmanaged gigabit Ethernet switches cascaded (heaped) together, assuming that there's no other traffic on the network. You'll have sub-1ms delivery times of such small frames with even consumer-grade switches provided that yours is the only traffic.
If there is other traffic then you'll start getting into the fun, non-deterministic world that is Ethernet.