I have an Fi-Shock electric fence energiser XP15E (Electric) for sale used for one year on 6 rolls of chicken fence in an open field. It can handle up to 22km of single strand fencing around a pheasant pen.
This does need to have an electric supply within about 100 metres for it to work.
Immaculate condition - Posted £130 or £120 collected from Oxford area.
I also have 3 rolls of electric fence for chickens available for £65 per roll which is It is 112cm tall and has 15 built in stakes, no damage but must be picked up from the Oxford area.