A suitable pumpkin bucket will be translucent under bright light. The goal is to be able to see the glow of a tea light through the walls of the bucket. Florescent buckets like these are also cool if you are using black lights.
Turn the bucket over and drill 1 large hole (1/2" to 3/4") in the center and 3 or 4 small holes (1/8-1/4") around the edge of the bottom. The small holes are for drainage if it rains.
I found LED tea lights at a local bargain outlet for 25 cents US each. The bottom of these has an on/off switch and unscrews to expose a coin cell, which lasts a few days.
Apply hot glue on all the raised edges of the bottom of the tea light. Don't get any into the switch mechanism.