Hello,
All of them can use the same crypto isakamp policy and same crypto ipsec setup but on the crypto map configuration you should change the ipsec peer and the crypto ACL.
As you also know you can only have one crypto map per interface so what you are going to do is just to add a new entry for the different site to site tunnels.
And finally create a tunnel-group for each remote site with their respective pre-shared key
Regards,
Any other question..Sure.. Just remember to rate all of my answers.
Julio
Julio Carvajal
Senior Network Security and Core Specialist
CCIE #42930, 2xCCNP, JNCIP-SEC