Not necessarily the best option, but Sony's centre direct has restocked on refurbished soundbars.
HT-SD35 for £109 (2.1 soundbar with dedicated subwoofer, good if bass is the only thing you care about)
HT-SF200 for £109 (rting rated this as one of the cheap soundbar best buy. not sure why)
HT-X8500 for £169 (one of the cheapest atmos soundbar, but TCL TS8111 could be better?)
HT-G700 for £259 (cheapest recent 3.1 soundbar from sony's offering)
They have few other more expensive ones, and older ones (with wired rear/subwoofer)