How can I restrict the version of the target DB instance in a SSIS package?
Create an initial Execute SQL Task in the Control Flow and use the following code in it:

IF ((SELECT CAST(SERVERPROPERTY('ProductVersion') as CHAR(2))) = 11)
    BEGIN
        SELECT 'TRUE' As Result
    END
    ELSE
        SELECT 'FALSE' As Result


You can of course do several things with this, one of the easiest and clearest for SSIS developers would be to store the results in a SSIS variable and assign the Precedent Constraint after the SQL Task to Expression and Constraint.

If the Execute SQL Task Succeeds and returns TRUE it will allow the rest of the execution, which could be a single package, part of a larger execution stream, or a master package. If it fails or returns FALSE your package stops... might be worth putting in another path for an alert message or log of this though.

You can also use (SELECT @@VERSION) LIKE 'Microsoft SQL Server 2014%'. I like this as it's a more familiar version nomenclature.