VS with Wildcard Pool set path to specific port

Create datagroup (uri_to_port) for uri to port mapping

ltm data-group internal /Common/uri_to_port {
    records {
        "/service1" { data "7070" }
        "/service2" { data "8080" }
        "/service3" { data "9090" }
    }
    type string
}

create app_pool with pool members with wildcard port and then use below iRule

when HTTP_REQUEST {
    # Default port if not found in data group
    set port_number 443

    # Get the URI path
    set uri_path [HTTP::path]

    # Lookup the port number in the data group
    set port_number [class lookup $uri_path /Common/uri_to_port]

    # optional logging
    log local0. "Routing to port $port_number based on URI $uri_path"

    # Get the list of pool members
    set pool_members [members -list app_pool]

    # Initialize a flag to indicate if a node is selected
    set node_selected 0
    
    # Iterate through pool members to find an active one on the specific port
    foreach member $pool_members {
        # Extract the IP address from the member string
        set ip [lindex [split $member ":"] 0]
        
        # Check if the node is active on the specified port
        if {[active_members -node "$ip:$port_number"] > 0} {
            # Node is active
            set selected_member "$ip:$port_number"
            set node_selected 1
            break
        }
    }
    
    # Check if a node was selected
    if {$node_selected} {
        #optional logging
        log local0. "Selected member: $selected_member"
        
        # Use the node command to forward traffic to the specific server and port
        node $selected_member
    } else {
        # No active members found, respond 503
        HTTP::respond 503 content "Service Unavailable"
    }
}

PS - This isn't tested iRule. Please test in non-prod environment before proceeding to PROD.