I was trying to order some of these when I noticed a strange thing.
I think there is a problem identifying which variations of the brick that vendors
have for sale.
Either that or the correct brick has not been identified in the set-inventories.
3002old TC comes in 36 sets and there are 411 available to purchase.
3002 TC comes in 1 set and there are 344 available.
That one set with 3002 TC is 1469, a shell helicopter with only one 3002 TC and
yet this one set accounts for 45% of the 2 x 3 Trans-Clear Bricks on BL. This
just doesn't seem likely to me.
PS
3002 has a couple more variations but I don't think they're relevant.
bhol03 doesn't have a TC colour.
3002f1 doesn't come in any sets apparently.