ive had a friend turn down a metal rod and thread a handle on the end and it was taking many-many dips to get a decent thickness, then cut the tentacles
ive tried the horizontal idea in the past but its hard to keep the plastic at the right temp, seemed like id get two or three dips before the plastic needed to be reheated
dont know how a mold with a cavity would work, since ive never tried but seems pricey since rtv aint cheap