Creating a dynamic one-to-one SNAT pool

How do I apply the pool to the SNAT?

you can use simple irule something like this. you also need to make sure server knows where to send return traffic e.g. routing, arp.

 configuration

root@(ve11b)(cfg-sync In Sync)(Active)(/Common)(tmos) list ltm virtual bar
ltm virtual bar {
    destination 172.28.24.10:80
    ip-protocol tcp
    mask 255.255.255.255
    pool foo
    profiles {
        fastL4 { }
    }
    rules {
        qux
    }
    source 0.0.0.0/0
    vs-index 6
}
root@(ve11b)(cfg-sync In Sync)(Active)(/Common)(tmos) list ltm pool foo
ltm pool foo {
    members {
        200.200.200.101:80 {
            address 200.200.200.101
        }
    }
}
root@(ve11b)(cfg-sync In Sync)(Active)(/Common)(tmos) list ltm rule qux
ltm rule qux {
    when CLIENT_ACCEPTED {
  scan [IP::client_addr] %*d.%*d.%d.%d c d
  snat 192.168.$c.$d
}
}

 trace

[root@ve11b:Active:In Sync] config  tcpdump -nni 0.0 port 80
tcpdump: verbose output suppressed, use -v or -vv for full protocol decode
listening on 0.0, link-type EN10MB (Ethernet), capture size 96 bytes
13:38:36.981475 IP 172.28.24.1.50638 > 172.28.24.10.80: S 2519421337:2519421337(0) win 5840 
13:38:36.981607 IP 192.168.24.1.50638 > 200.200.200.101.80: S 2519421337:2519421337(0) win 5840