Just for info, I got the price for Colins 6em7 TX (well, a generic 5k 50ma amorphous TX in fact, so it can be used for 45's as well)
OPT is 10W Eur 268,- a pair 50mA 4+8 Ohm 5K amorphous potted
There is tax at 19% and shipping to add to that, so it should be about £250 I guess for the pair.
Or to compare to the guesstimate Clive made, thats £190 + tax + shipping