The Sup7E has 4 10-gig ports, but they have 1Gig transceivers in them.
It was my understanding that one could use the 1G or 10G ports on the supervisor in addition to 1G or 10G ports on line cards. I have two ports on each of two WS-X4748-RJ45-E blades in each chassis in the VSL in addition to two ports on each supervisor - or at least that is how I configured things.
I essentially have what is shown Figure 5-5 VSL Topology Example in your link.
Difference #1 is I'm using 1G links from the Sups and have the two active line cards instead of just one.
I will have my customer obtaing the SFP-H10GB-CU1M transceiver/cable combos and be done with it.
I do understand the need for 10G links. All of the above is set up for burn-in and infant failure detection.