Alternative Balsa Filler?

I've used Hobbico HobbyLite Filler before to fill gaps and some balsa pieces.
For me, I still find it easier to use brushable CWF. But in rocketry this HobbyLite Filler does have some uses.

On the left is the red label. The filler is a tan balsa color.
The blue labeled tubs have white filler.
Both are water soluble.
Online price is $8.75 for an 8 oz tub before shipping.

On TRF, Dave Carver wrote:
"DAP Fast 'N Final Light Weight Spackling is the same stuff except it's 1/3 the price as the hobby filler. If the tub you get feels heavy it's the wrong stuff."
Online price is $5.80 for the 8 oz. tub.