Perhaps you could generate an Array of random numbers and then use the of: message to repeatedly read from that Array? For example, something like this:
| r |
r := Random newForKymaWithSeed: 879.
(1 s tick nextIndexMod: 64) of: (1 to: 64 collect: [:i | r next])
If you'd like to be able to change the contents of the Array, you could instead use something more like the following, in which case you could use !Trigger each time you'd like to generate a new set of 64 random values:
(0.2 s tick nextIndexMod: 64) of: (1 to: 64 collect: [:i | !Trigger nextRandom * 36 nn + 48 nn])