You can use the INDIRECT function to change the reference to a dynamic named range in a formula in cell G. Simply enter the name of the named range you want in cell $K$2 (for example, Kin2_), then change the formula as follows:
:=INDEX(INDIRECT($K$2 & "_"), MATCH($D6, Item, 0))
The formula will now automatically use the named range specified in cell $K$2.