A koko boost can brighten up your amp on the mid side. Not a treble booster, per say, but will add some treble and upper mids with the mid switch in the left or middle position. I think the clean boost side adds a little sparkle as well, but not much.
I love mine. I'll probably always have the koko.
I've not tried the TC Spark Booster, but something else you might could look into.