There are half a dozen internet firms offering service exchange reconditioned turbos for £350-£700. TurboTecnics springs to mind, but there are plenty more. These generally come with a year's warranty. Last time I had a turbo on and off it cost me £70 for labour.

Asssuming that your £7775 is a typo and you meant £775, this is in the range but it is worth shopping around. If the £1000 is for a genuine, brand new, straight from VW turbo then this doesn't look too bad. You can always phone the parts department to find out the retail price and assume another £50-100 for labour. Whatever way you go, make sure the price includes a new oil feed pipe connector, since these tend to get blocked with crud and it might be why your original failed.