Rate limiting and pool redirection

We've got a client-facing application server pool sitting behind a Brocade SLB. Everything works fine, but we are vulnerable to clients who cache our product availability and overload the farm, which causes disruption to all clients. Currently we manage this manually, by creating redirection rules based on source IP. Is it possible with F5 products (and presumably iRules) to configure a transaction rate limit, above which specific clients (identified by IP address) can be transparently redirected to a second server pool, thereby protecting "well behaved" clients?