£250 sounds reasonable, it's sometimes possible to get a good one with the same lens, prism & grip for a bit less and you have to compete with dealers who sell them for not a lot more typically £300-£350 but with a warranty.
I bought mine for a steal. 300 USD for an ETR, ETRS, ETRSi, two speed grips, 75mm EII, 75mm MC, 40mm f/4, 150mm f/3.5, two 220 backs, two 120 backs, polaroid back, two bellows shades, and some filters...all in excellent condition.