Two plants cost me about £4 including shipping.
Step 1. Unwind the stem and and separate the plant pieces, this gave me 8 pieces from one plant.
Step 2. Clip the pieces off of the wire stem, leaving a small length of wire on the end.
Step 3. Drill a hole in a mdf base and glue the plants to the base.
Step 4. Texture the base.
So from 1 plant I got 8 nice looking cacti, about 4.5" high, for my Western Gunfight games for about £2.50 in total.